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Aktivite bazlı kalite maliyetleme sistemi

Activity based quality costs system

  1. Tez No: 64702
  2. Yazar: BEYTULLAH ÖMER MUTLUGÜN
  3. Danışmanlar: YRD. DOÇ. DR. NECDET ÖZÇAKAR
  4. Tez Türü: Yüksek Lisans
  5. Konular: İşletme, Business Administration
  6. Anahtar Kelimeler: Belirtilmemiş.
  7. Yıl: 1996
  8. Dil: Türkçe
  9. Üniversite: İstanbul Üniversitesi
  10. Enstitü: Sosyal Bilimler Enstitüsü
  11. Ana Bilim Dalı: Belirtilmemiş.
  12. Bilim Dalı: Belirtilmemiş.
  13. Sayfa Sayısı: 237

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an E SSTÂKIIİUL yiMlWE^ilT SOSYAL BİLIML D DP QO STOTUiü YÖKSEtC LİSAMS TE ES@MronBİk üitendiı B“ Öm@r ÜUTLUSÜS OD ? D E Tfe Danışmanı : Yrd. D®e”Dr. Neetifet ÖZÇÂKÂR.ran ittiSUMMARY QUALITY COSTS An American executive related to one of the authors how, in the early 1 970's, he visited a Japanese factory where a slogan in enormous Japanese characters covered a whole wall of the foyer. On enquiry, he found out that the message spelt, broadly, that“Quality is the battle - ground of today !”The incident happened some years ago, and western competitors did not immediately realise that they were engaged in a war; by the time they did, much ground had already been lost; nor can we be confident that the retreat is yet over. Japanese businessmen realised very early in their country's reconstruction after the war that quality not only sells, it pays! In combating competition from both east and west, traditional industry suffers from two self - inflicted handicaps. These are the ideas that:“Enhanced quality carries a price penalty”, and,“Good and poor quality cannot be accurately measured in monetary terms”. These assumptions are embedded in traditional management thinking, but neither has any foundation. Quite the contrary. However, the ideas have distorted the ways in which many companies have been, and are still being managed. This in turn has reduced their profitability, the level of investment available to them, and their ability to respond to competition. To know your quality costs, and to act in accordance with that knowledge, is crucial. Non-conformance costs are the measure of your success in achieving quality. Senior management evaluate all issues in terms of costs and revenue, so if quality issues are not presented in monetary terms they will not receive their due attention. What you are seeking is an investment in defect prevention. The companies that will win are the ones whose quality assurance is not only effective, but also cost efficient. Furthermore, the outcomes of many companies' strategic decisions are affected by quality costs, yet they are not taken into account. No wonder the outcomes are not always the desired ones ! The purpose of this thesis is to enable you to ; * Apportion quality costs into conformance and non-conformance costs, and their appropriate sub-divisions. * Identify and collect approximate quality cost data for your company's operations. * Analyse, present and draw conclusions from the data. * Make decisions based upon the data. C:\aa\tez\om-O00.doc 1/18 B-000What are Quality Related Costs ? What is quality ; Quality of a product or service is totality of features which determine its fitness for the use intended by the customer. It is customer satisfaction. It is conformance to the requirements. These and many other definitions in a similar vein have been given, and all of them are true. All relate to fulfilling the customer's needs, and these needs include affordability, delivery at the right time, safety, reliability and after - sales support. Grade and level of quality ; Neither a Formula 1 nor Rolls Royce is a“better quality”car than a Ford Escort. They are simply aimed at different customer needs. In terms of benefiting the greatest number of customers, and making the most overall profit for its manufacturer, the Escort is the clear winner. Therefore we have to distinguish rigorously between grade and quality level. Grade is what makes an Escort an Escort and not a Fiesta or a BMW 3181; price, availability, dimensions, performance, fuel economy, trim level, etc. Quality level is what makes a purchaser satisfied or dissatisfied - whether they received what they expected. Unavailability of an advertised colour or optional feature, rust, rattles, breakdowns or conflicting guidance on whether or not the car can run on unleaded petrol, are all shortfalls in the quality level. Quality - related costs ; Quality costs are the sum of : * The money spent in attempting to achieve a quality level of 1 00 % customer satisfaction. * The money wasted through failing to achieve the 1 00 % quality level. Why you should you try to achieve 100 % success? Isn't a lower level enough ? No! This is because ; * 1 00 % conformance is more profitable; it is always cheaper to“do it right first time”. * If you don't provide total customer satisfaction a competitor probably will. However, in a democratic, capitalist society you are still free to follow your own path. As Dr. W. Edwards Deming (after whom Japanese industry named its annual quality price) said,“Survival is not compulsory!”C:\aa\tez\om-000.doc 2/18 B-000The opportunity to save costs ; Even the best companies ( in terms of quality ) still spend large amounts of money due to a quality level of less than 100 %. For the more typical organisation the sums lost avoidably through inadequate quality are vast. In manufacturing industry these are identified mainly as“scrap”,“wastage”,“rework”etc. They may easily represent 25 % of sales value. In a service industry they are recognised as“mistakes”and“time-wasters”. In some service companies it is estimated that up to 60 % of employee time is spent double - checking, rectifying and apologising for errors. The opportunity to measure costs ; One of the saddest results of the confusion between quality grade and quality level is the mistaken idea which has arisen that quality is exclusive, in short supply, hard to define or measure, but clearly expensive. In reality, 100 % conformance to the quality requirements is definable - hence measurable, controllable and manageable. It is the cheapest, as well as the best, way of doing the job. Management accountants do an indispensable job in providing the cost information on which executives' decisions are made. Unfortunately, since the myth that quality is not measurable in cash terms is still widespread, the accountants are not geared to providing this data on a routine basis, if at all. There is another consequence, equally dangerous. Due to the absence of data from the recognised source, quality professionals in the organization are not conditioned to providing information on quality - related problems and opportunities in cash terms. They do not speak the same language as the boardroom, and so major decisions on quality issues may be made on incomplete data or on“gut-feel”rather than on quantitative facts. THE COSTS OF QUALITY AND“UN-QUALITY”The most widespread way of looking at, categorising and analysing quality costs has been in use for some 20 years. It was first formulated publicly by the American Society for Quality Control (ASQC), and later adopted by the British Standards Institution (BSI). The latter currently publish their presentation as BS 6143: Part 2: 1990. It is entitled“Guide to the economics of quality Part 2. Prevention, appraisal and failure model”. Conformance and non - conformance costs ; Quality costs fall into one or other two major categories. One category is that of the costs deliberately incurred in efforts to maintain or improve quality. In the prevention / appraisal / failure model, this is called the“cost of conformance”. It includes the costs of both prevention and appraisal activities. The other category is that of the costs suffered as a result of bad quality. This is called the“ cost of non-conformance”, and represent the failure costs. C:\aa\tez\om-000.doc 3/18 B-000I wish to stress that the cost of bad quality normally heavily outweigh the costs invested in quality maintenance and improvement. Use of quality costs; Although most companies still have little idea of their total quality costs, this information would be of great value. If quality cost figures are available you can: - Compare the quality cost performance of one plant or production line with another. NOT to berate people, but to learn and to transfer successful techniques and ideas. - Monitor trends in quality costs. - Budget future quality conformance costs, and set improvement goals. - Decide which quality costs need to be reduced, and where more investment in prevention could produce savings. - Decide on strategy. Quality cost estimates When manufacturing organizations have carefully examined their quality costs, they have typically found them to be as much as 25% of sales value, and this value is quoted by Crosby. A similar pattern applies to organisations which provide a service rather than manufacturing a product. In the same reference, Crosby quotes a typical quality-related cost figure of 30% of operating costs. The first attempt to estimate quality-related costs is notoriously prone to under-estimation. Crosby suggests 30% of the true value. Categories of quality cost (prevention, appraisal, failure model) Quality-related costs comprise both voluntary costs of achieving a desired level of quality, and also the involuntary costs of failing to achieve it. These are respectively called the costs of conformance, and of non-conformance; C:\aa\tez\om-000.doc 4/18 B-000sometimes also cost of quality“ and ”cost of UN-quality“. Both pairs of names are worth remembering, because they remind us to distinguish between the ”good“ costs which are incurred in actively pursuing quality, and the ”bad“ costs which are the penalty of failure to achieve the required quality. Each category of quality cost can be broken down into two further divisions as shown in figure 1. Ql Vim HI! MID] COSIS i A f COMORMWI İSVûh I \PPK\ts\I İOS1S ”} JKfcVUM KIN (OS IS I NOVCOMORMVM I I fV|*hMMRi COSIS COS IS Figure 1 : Categories of Quality Costs Costs of Prevention“The cost of any action taken to investigate, prevent or reduce defects and failures. Note: prevention costs can include the cost of planning, setting up and maintaining the guality system.”Costs of appraisal“The cost of assessing the quality achieved.”Note: appraisal costs can include the costs of inspecting, testing etc. carried out during and on completion of manufacture.“ Failure costs - internal ”The costs arising within the manufacturing organisation of the failure to achieve the quality specified. Note: the term can include the cost of scrap, rework and reinspection, and also consequential losses within the organisation.“ C:\aa\tez\om~000.doc 5/18 B-000Failure costs - external ”The costs arising outside the manufacturing organisation of the failure to achieve the quality specified. Note: the term can include the costs of claims against warranty, replacement and consequential losses of custom and goodwill.“ Elements within quality cost categories Several elements can be identified within each of the cost categories. There is an ”official“ list which appeared first in ASQC (1970) and was then adopted by BS 6143 (1981). A revised version appears as appendix A in BS 6143: part 2: 1 990. This is summarised below. Prevention costs ”These costs are incurred to reduce failures and appraisal costs to a minimum. The usual categories include the following“. (a) Quality planning (b) Design and development of quality measuring and test equipment (c) Quality review and verification of design (d) Calibration and maintenance of quality measurement and test equipment (e) Calibration and maintenance of production equipment used to measure quality ”These costs are incurred in initially ascertaining the conformance of the product to quality requirements; they do not include costs from rework or reinspection following failure. Appraisal costs normally include the following“. (a) Pre-production verification (b) Receiving inspection (c) Laboratory acceptance testing (d) Inspection and testing C:\aa\tez\om-000.doc 6/18 B-000(e) Inspection and test equipment (f) Materials consumed during inspection and testing (g) Analysis and reporting of test and inspection results (h) Field performance testing (i) Approvals and endorsements (j) Stock evaluation (k) Record storage Failure costs ”These are subdivided into internal and external failure costs: internal costs arising from inadequate quality discovered before the transfer of ownership from supplier to purchaser and external costs arising from inadequate guality discovered after transfer of ownership from the supplier to the purchaser.“ ”The internal failure costs include the following (a) Scrap (b) Replacement, rework or repair (c) Troubleshooting or defect/failure analysis (d) Reinspection and retesting (e) Fault of subcontractor (f) Modification permits and concessions (g) Downgrading ( h ) Downtime“The external failure costs include the following”(a) Complaints (b) Warranty claims (c) Products rejected and returned (d) Concessions (e) Loss of sales (f) Recall (g) Product liability COLLECTING QUALITY COST INFORMATION The collection and reporting of the costs incurred in running an operation is recognised as part of the duties of the finance department, usually of a specialist section known as“cost accounting”or“management accounting”. However, since historically, guality-related costs have not been treated as a key issue for management attention, costs have not been collected routinely in the form we have just been outlining. Indeed, you may well find it difficult to have them extracted and apportioned under the kinds of heading we have been discussing. C:\aa\tez\om-O00.doc 7/18 B-000Because of this, it is often the QA department which takes the first steps towards producing an estimate of quality-related costs. We say“estimate”because the initial attempt is bound to be approximate, and everyone should treat it as no more than a pilot study. MONITORING QUALITY COSTS we have stated earlier, the purpose of collecting quality- related costs is: To make comparisons, to indicate how well an operation is controlling costs, and to show where attention is most needed. To provide a baseline against which to set goals and to measure improvements. To make it easier to identify these patterns, there are several convenient ratios and figures of merit which can be calculated. Figures of merit When comparing quality costs in different plants, or on different occasions, a figure of merit enables you to make comparisons on a like basis. The particular ratio you use will depend upon the factor you want to highlight, e.g. quality costs in relation to labour utilisation, sales value, production costs etc. Some of these ratios are: (a) Labour-based: internal failure costs direct labour costs (b) Cost-based: total failure costs manufacturing costs (c) Sales-based: total quality costs nett sales (d) Unit-based: total quality costs units of production (e) Added value-based: total quality costs value added C:\aa\tez\om-O00.doc 8/18 B-000The particular ratio you might wish to use would depend upon your Particular business and the aspect of financial performance you wish to focus on. For example, a labour-intensive service business which wants to improve utilisation of personnel and reduce human error might direct attention to trends in the labour-based ratio. On the other hand, it would be most misleading for a manufacturing company in the process of automating its processes to use this ratio, since the reduction in number of employees would change the ratio regardless of any quality improvement. Failure/ Appraisal / Prevention ratio This is very often presented in the form of a pie chart. (See Figure 2.) Typically, failure costs are the largest proportion, then appraisal, with prevention costs the least. The major part of the failure costs may be internal or external, depending on the industry and its market. PREVENTION 40% Figure 2 Typical raios of quality costs PRESENTING AND USING QUALITY COST INFORMATION Quality-related costs are worth collecting only if there is the intention of taking some action as a result. (Otherwise you are wasting still more time and money! ) Such actions may be aimed directly at reducing the costs, or at making people aware of the costs and their importance, as a step towards the same end. C:\aa\tez\om-O00.doc 9/18 B-000The first quality cost report It is unlikely that the pilot study will disclose the full extent of quality-related costs. Crosby suggests that a typical first estimate rarely arrives at more than 30% of the true value. Even so, it is possible to create first disbelief, and then alarm, and afterwards, hopefully, a breakthrough in quality awareness as people face the facts that: - Quality is not vague, but is measurable in monetary terms. - It impacts the whole company, not just the QA department. - Bad quality hits where it hurts most - on the bottom line. - Everyone's budget suffers to some degree. - Substantial savings are waiting to be made. - Insufficient resources have been invested in prevention in the past. Looking for cost savings The savings may well be the result of corrective actions, but the easiest way to identify these actions is by investigating the causes of failure costs. Setting up a quality improvement team or task force is often advocated. This should be multidepartmental and multi-disciplinary. Some skill and insight is necessary to select the priorities for action, particularly since the first task to be tackled should be an unambiguous success if the momentum is to be maintained. Points you should bear in mind are: As stated above, the first task undertaken should be one where complete success is confidently expected. Don't direct much effort to obsolescent processes or products near the end of their lifespan. - More benefit may be gained by smaller savings achieved on recently launched products for which a long and successful future is predicted; not least because their acceptance and future sales will be influenced by customer satisfaction in the early stages. C:\aa\tez\om-000.doc 10/18 B-000- The likely ease or difficulty of solving a problem must be taken into account as well as its absolute magnitude. - Even if a cure is found to be impracticable due to expense or disruption of production the objective should not be abandoned - an opportunity to implement a solution may arise later, e.g. when a product is redesigned or a production line re-equipped. - A small improvement in yield on a high-volume line will offer more savings than a larger percentage improvement on a lower-volume line. - Task force membership does not have to be fixed - its personnel can be changed, its scope broadened, or it can be disbanded when it has served its purpose. Maintaining the impetus In a small company it may be possible only to calculate and review quality costs annually. This will show the progress being made during the past year, and where effort should be concentrated during the forthcoming twelve months. In a company with larger resources, typically every manager having budgetary responsibilities receives a detailed monthly account of expenses and manufacturing costs. It should then be possible to report and monitor quality cost data on a similar basis. Quality cost reporting does not in itself solve any problems. It supports and intensifies other company-wide quality improvement activities by converting“quality problems”, liable to be seen as the province of the QA department, into“profitability problems”recognized as everyone's priority concern. C:\aa\tez\om-O00.doc 11/18 B-000LOW IDEA DESIGN PROTOTYPE PILOT PRODUCTION INSTALLATION SERVICE Figure 3 Opportunity versus difficulty of change THE PROCESS COST MODEL The“process cost model”draws on a concept which is familiar in the“Total Quality Management”(TQM) approach to quality assurance. This involves breaking down all the activities of the company into interlinked“processes”. Each process has inputs and outputs, both desirable and unwished for; the desired inputs come from“suppliers”and the the desired outputs are delivered to“customers”; see figure 4. The suppliers and customers may be outside the organisation being considered, but in the case of many processes they are internal suppliers/ customers. CONTROLS INPUTS PIMM»' OUTPUTS RESOURCES Figure 4 Process cost model C:\aa\tez\om~000.doc 12/18 B-000Process cost elements These derive from, and can be recorded under: People Equipment Materials Environment The process cost model categorises quality costs as conformance and non conformance costs, but not in the way we have done. The classification we have used in this report was derived from the prevention/appraisal/failure model: Conformance cost = prevention + appraisal costs: Non-conformance cost = (internal + external) failure costs. By contrast, the process cost model defines the terms as follows : Cost of Conformance (COC)“The cost of operating the process as specified in a 100% effective manner. This does not imply that it is an efficient, nor even necessary process, but rather that the process, when operated within its specified procedures, cannot be achieved at a lower cost. This is the minimum cost for the process as specified.”Cost of Non-conformance (CONC)“The cost of inefficiency within the specified process; i.e. over resourcing or excess costs of people, materials and equipment arising from unsatisfactory inputs, errors made, rejected outputs and various other modes of waste. These are considered non-essential process costs.”Advantages and disadvantages of the process cost model An advantage claimed is that costs do not have to be identified and categorised as prevention, appraisal or failure and which, it is argued, can be difficult and unsatisfactory to do. C:\aa\tez\om-000.doc 13/18 B-000Categorisation may be unnecessary, but that identification is essential. Categorisation is helpful because they remind the analyst that costs classed as failure costs are all potentially avoidable, and as that situation is approached so also do appraisal costs become avoidable. The complete analysis of a company's activities into interlinked“processes”, accurately and without duplication (and consequent double-counting of costs), may be more onerous than the traditional categorisation of quality costs. Furthermore the inclusion into the COC of the running costs of“inefficient or unnecessary”processes but running exactly according to the book appears to hide the inefficiency. A repair station with no waiting time, no wasted repair materials or no ineffective repairs would incur no CONC, yet its only reason for existence would be a copious flow of rejected work from the line. To make matters worse, it has been suggested by at some writers that“standard”times, yields, costs etc. can be taken as the basis of the COC. Thus even the COC would contain hidden yield losses, etc. ' In terms of highlighting opportunities and needs for quality improvement we consider the process cost model is a retroqrade step. (Using the same categories of people, equipment, materials and environment for analysing what is happening in a process is, of course, an excellent aid to understanding and improvement.) THE CONCEPT OF ECONOMIC BALANCE OF QUALITY British Standard BS 4778 defines economic quality as:“The economic level of quality at which the cost of securing higher quality would exceed the benefits of the improved quality”. This concept was illustrated in the original BS 6143 (1981) by the diagram reproduced in figure 5 C:\aa\tez\om-O00.doc 14/18 B-000Figure 5. Graph of Quality costs taken from British Standard BS 6143 (1981). MEASURE OF QUALITY (Quality Level) Although most commentators now deny that a point of minimum quality cost exists whilst defective product is still being produced, the idea of an“economic balance of quality”is so rooted, and so harmful, that it still warrants discussion. Its justification as presented in figure 5 is however ambiguous, misleading, and.in most practical cases erroneous. We will present the traditional view first, and then challenge its validity. The traditional presentation You will recall that quality costs can be divided into the costs of conformance and non-conformance and these in turn subdivided into“appraisal + prevention”, and“external failure + internal failure”costs respectively. Having accepted these definitions, the argument proceeds as follows: - If there is little or no investment in conformance costs, quality is likely to be poor: i.e. non-conformance costs will be high. C:\aa\tez\om-O00.doc 15/18 B-000- If more expense is invested in conformance activities; nonconformance costs will decrease, quality will improve. - The more quality is improved, the harder it will be to produce further improvement. One might find for example that it costs 25p to eliminate each residual defective component, whereas the sales value of the component is only 22p. - At such a point, the conformance cost introduced is greater than the non conformance cost it is intended to eliminate; improvement activity becomes uneconomic. - Hence there exists a point at which the sum of conformance and non conformance costs is a minimum. This is the point of“Economic Quality”. Producer and supplier must accept the economic necessity for the incidence of defective items which remain at this point. Limitation of the“economic balance”model The first thing to note is that the“measure of quality”(Quality Level) is not defined. What is the measure being represented? A variant of this diagram shows“proportion defective”, from 100% at the origin to 0%, and we will assume this to be the intention of figure 5. Secondly, examples used to illustrate the argument, like the 22p component one which we have given above, assume that the loss cannot exceed the intrinsic value of the rejected item. But suppose the defective unit was installed in some instrumentation, the malfunction of which delayed a space launch? Or a heart pacemaker which failed? Or if its failure caused the purchaser to find a different source of supply? Then, of course, we have loss of customer goodwill and product liability costs to consider. Thirdly, the traditional model ignores the time element. Preventive actions have no immediate impact on non-conformance, but once they are in place they can save non-conformance costs throughout the market life-cycle of the product without further investment. C:\aa\tez\om-000.doc 16/18 B-000Next, the argument and diaqram fail to differentiate between appraisal and prevention, or between internal and external failure costs. As has been stressed many times in this report, appraisal and prevention have guite different effects on nonconformance costs. Finally, we can see from everyday examples that we can have a very high level of quality at modest cost. According to the graph, for the very low defect rate we expect and get for milk (or Whisky, according to your taste) the cost, ignoring taxation, should be very much greater than we actually pay. An alternative representation As we pointed out earlier, a serious limitation of the traditional representation is that it takes no account of changes happening over the course of time. Also, there is really no need to define or plot a quality level as such; we can say that the external failure cost is itself a measure of the quality as perceived by the customer, or that the total failure cost is the indicator of its level to the manufacturer Consequently the form of presentation most favored in practical situations is simply to plot the total cost of quality, and its four components against time. We give an example in figure 6. Such a plot allows improvements and setbacks to be easily assimilated visually; after all, this is the information the, organization is looking for: - Are our external failure costs being eliminated, since these represent our quality as seen by the customer? -Are our total failure ( non-conformance ) costs being reduced, since this represents our internal measure of quality? -Are we achieving the two previous goals increasingly effectively? (i.e. reducing total quality-related costs by using prevention rather than appraisal). C:\aa\tez\om-O00.doc 17/18 B-000TOTAL QUALITY RELATED COSTS QUALITY AWARENESS AND IMPROVEMENT Figure 6 An example of Quality costs over time C:\aa\tez\om-O00.doc 18/18 B-000

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