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I’m not going to join the ‘let’s knock Toyota’ brigade, don’t worry. Enough people are filling that role already. In fact, I drive a Toyota (an older model) and I’ve been very happy with it, and one of my clients has got one too and is equally happy. My point is how easy it is to go off the rails. Those of us who work in Quality are only too aware of the huge reputation that TPS – the Toyota Production System – enjoys. It is taught in colleges and universities and vocational training institutes world-wide and is usually seen as the gold standard of ‘how to do manufacturing properly’. But gosh how they have messed up with sticking accelerators and dodgy Prius brakes. The company that is so good at taking Preventive Action suddenly has some major Corrective Action problems and a PR disaster on its hands. So here’s the question: Do you have the equivalent of Toyota’s sticking accelerators and bad brake profiles lurking in your design or production areas? How do you know? What can you do to reduce the risk of a similar nasty surprise hitting your production? If Toyota, with its world-class manufacturing and quality, can have these sorts of problems, can’t we all?         There is an assumption, held dear by many people, that apparently random events really are random. If you’re manufacturing 800 widgets a day, and 1 in 100 is faulty when you test it, then every hour you get a test failure and the production line klaxons go off like in Stephen Fry’s ‘QI’ programme. It isn’t like that! Faults don’t neatly line themselves up at regular intervals; that would be too easy. They hunt in packs. I once worked for a professional audio equipment company that had produced exactly the same public address amplifier for many years. It always worked and there were negligible failures during production test… until one Tuesday when all Hell broke loose. Every single one that went into test exploded. The electrolytic output capacitors took off like rockets and left the ceiling covered in that nasty orange fluffy stuff. Not one amplifier worked. The problem was difficult to find because, despite our initial assumptions, they had all been made correctly; there was no assembly error or component fault. As part of the circuit design a pair of components – signal diodes – had been used to set the amount of current that flowed in the amplifier’s output circuit. Now, the specified diodes could, in theory, have had a wide range of electrical characteristics and still have been perfectly normal, acceptable, working diodes. Their manufactured tolerance range was very wide. in practice they had always been smack bang in the middle of the possible range of values. Without fail. Until that point… The batch of diodes bought that time round was different. They were still within their manufacturer’s specification, but only just. They were right on the edge of the permissible limits. Diodes like that had never been seen before by the company and no-one had tried them to see if the circuit still worked, which is a pity because such a test would have shown that it didn’t work – in spectacular fashion – when such an ‘on the edge of its limit’ component was used. The cure was easy when the problem was found but it still stopped production dead while the investigation was done and the fix designed and proven. It was a costly problem. And that’s why production sometimes stops dead rather than limps along with a higher-than-you-would-like defect rate. Problems are not uniformly distributed throughout the population, they bunch or cluster as they are dependent on unusual characteristics of batches of components, or wear on a certain machine, or a particular operator not doing things exactly like the other operators; the classic ‘Friday afternoon job’. Problems bunch up and because of that they can stop production dead. So what can you do about it? There are a host of techniques that can minimise the risk of nasty surprises in production. Theoretical techniques such as tolerance analysis or Monte Carlo analysis are used, and modelling or simulation is done to identify the sensitive parts of the circuit and see what happens if worst-case toleranced components are used. Sometimes you deliberately build a prototype with parts that are slightly out of specification, in the worst possible combination, to see how it reacts. You vary parameters such as supply voltage or temperature. You do Failure Mode and Effects Analysis (I’ll talk more about this another time). A particular favourite technique of mine is to use HALT testing, and HASS as well if it’s commercially justified. You use Statistical Process Control in production to spot an impending problem early, maybe before it actually becomes a problem, and you do design centering to give yourself the best chance against varying component and process tolerances. You review your incoming goods inspection or test processes – or, better still, your suppliers’ outgoing goods inspection or test processes – in the light of the performance you really do need… and so on. In other words, you take a range of preventive actions that help to minimise the risk of production grinding to a halt. In Radio 4’s Today programme this morning the team were pondering on double-yolk eggs. The probability of finding a box full of double-yolks, at random, is 1 in many millions or even trillions… So why had so many listeners found six in a box? The answer is not only that some hens produce far more than their random quota, but that factory workers check eggs against a strong light and put double yolks to one side; the ‘random event’ of a double-yolk in an egg box is, in practice, anything but random. What ‘random’ surprises might you encounter in production? How have you minimised the risk? What more could you do? Until now I’ve been using the WordPress user interface. It’s a little clunky but you get used to it. However, today I was introduced to the joys of Microsoft Live Writer by the IT Manager at one of my clients and this is my first go at using it. And, I have to say, it’s a great deal easier to use than the built-in editor so dear Rob has come up trumps again! Of all the quality ‘gurus’ I find the late Philip Crosby one of the most readable. In his book ‘Quality is Free’ (Mentor 1980, ISBN 978-0451625854), which I can thoroughly recommend, he advocates the use of a simple tool to show where you are in the quality management spectrum; he calls it the Quality Management Maturity Grid. The grid is a simple 6 x 6 matrix that shows different stages of maturity of the company’s quality management against six different quality management categories (management understanding of quality, problem handling, cost of quality, etc). The lowest stage of maturity is called ‘Uncertainty’ – the organisation is inexperienced, quality management is a low priority and reactive, etc – then as quality management matures it goes through the stages of ‘Awakening’, ‘Enlightenment’, ‘Wisdom’, then the highest level, ‘Certainty’. Each point – maturity versus category – on the grid has a brief description of how that combination appears in the company; for instance, in the ‘Uncertainty’ stage, Problem Handling looks like “Problems are fought as they occur; no resolution; inadequate definition; lots of yelling and accusations.” If that sounds like your company then I’m sorry to hear it and you are at the ‘Uncertainty’ stage for Problem Handling! Here’s the grid (I know it’s difficult to read in some browsers as it’s shown below; you can either make your browser window a lot wider or click on it a couple of times to see it more clearly):
You use it by asking a number of people to assess the company; the more the merrier from different levels and roles across the company as it helps to give a more complete picture. Each gets a copy of the grid and makes a subjective judgement about which Stage the company is at for each category; they mark the grid in the appropriate position. It is important that they are very honest in their assessment; make a point of this with them. (By the way, you may find Cost of Quality a bit tricky to estimate if I don’t explain what it really means; sorry about that, I’ll have to blog about it another time. In the meantime, have a look at Jim Wells’ excellent description here.) The total score is obtained by adding up the scores for each category; Stage 1 ‘Uncertainty’ gives a score of 1, Stage 2 ‘Awakening’ = 2, Stage 3 = 3, etc. The minimum score is therefore 6 (all categories are at ‘Uncertainty), and the maximum is 30 (all are at Certainty); I know of no company that is at 30 so if you really are there please get in touch as I’d really like to meet you! It is really interesting not only to see the scores for each category (as well as the total), and the arithmetic mean across all the assessors, but also to see how individuals from different departments or roles in the company mark each category; big variances in scores indicate that people see the company as being very different in this area – why is that? Is the high score or the low score more appropriate? What needs to be done about a low score from just one part of the business? It can be a fascinating exercise. The thing I particularly like about the Quality Management Maturity Grid is that it is (a) very quick and easy to use, (b) insightful – it makes you think, and (c) – most important – it doesn’t just show you where you are but, also, what your company would have to be like to get a higher score; it therefore acts as your route-map for strategic quality and helps you plan your quality improvement initiatives so that you move steadily towards the right in the grid. ‘Lean’ means fat-free or thin or containing little waste, doesn’t it? (Appropriate for just after Christmas…) The answer is yes, and it’s one of the most recent trends in quality and management that started on the factory floor with Lean Manufacturing and has spread to other areas such as Lean Six Sigma and Lean Software Development. In fact, Lean can be applied to all business activities – the Lean Enterprise. Companies that have successfully implemented Lean claim huge improvements in productivity and costs – often several tens of percent – so I thought it was worth talking a little about. The Lean concept comes from the famous Toyota Production System (TPS) in the late 1980s. It works on the principle that any activity which does not add value to the product (or service) that goes to the end customer is wasteful and should be eliminated. Lean takes the customer perspective. The objective is to create more customer value, i.e. things the customer is willing to pay for, using fewer resources. It aims to reduce waste throughout the entire ‘value stream’ (all the business processes and operations used to deliver value to the customer, including the supply chain from raw materials to finished goods) – whether this is waste in materials, energy, time or effort – so is a very ‘Green’ initiative. To be successful, Lean needs a long-term change in the way a company operates – ‘Lean Transformation’ – and is a process of continuous improvement; Lean is a journey not a destination. It needs to involve everyone from top management to the factory (or office) floor, with a special emphasis on the latter as that’s where the responsibility and authority is delegated to and where the real benefits come from. Within Lean Manufacturing, seven different types of waste have been defined:
The aim of Lean is to eliminate these wastes and, in fact, to eliminate all non-value-adding work by changing the company’s processes, procedures and systems. Non-manufacturing processes have their own types of waste that are different to manufacturing but to which many of the same principles apply, which is why you now see Lean thinking applied to Six Sigma, Product Development, Logistics, Healthcare, the Enterprise, and so on. For instance, take the office process of Customer Sales Order processing: Where do customer orders get delayed and how can these delays be eliminated? How much time is wasted correcting errors in the orders and how can errors be prevented? Is any paperwork (or e-forms or emails) unnecessary? Are there any unnecessary stages of approval to go through (but all the necessary ones)? Does information flow erratically (e.g. the same form is handled several times by the same person) and how can this be made smoother? …and so on. Wasted time can be difficult to identify, so many companies specifically focus on reducing time as a key driver of Lean Implementation; agility and Lean go hand in hand. There is a also lot of work done on the planning of processes to avoid overloads or unreasonable demands, on eliminating work via improved design, and on improving the ‘smoothness’ of flow of information, processes and materials. Being customer-focused, the emphasis is on agile ‘pull’ processes that provide goods and services only when the customer needs them, not when the supplier would like to provide them. Lean isn’t a quick fix. I would love to be able to write a 500 word ‘just do this’ blog and see you turn your company into a Lean one overnight, but I can’t; it’s a big subject and there’s no simple workbook solution. This is not to say that individual tools and techniques, including quick fix ones, can’t be used within Lean. There is a key role for many different tools and techniques such as Six Sigma, Kaizen, Kanban, 5S, 5 Whys, Poka-Yoke, Just-In-Time (JIT), Statistical Process Control (SPC), Zero Defects (Right First Time), and so on. However, their use does not automatically result in a Lean organisation, they are merely tools to be used where appropriate. Lean is a way of thinking. It involves cultural change and that can be difficult and time-consuming. But Lean Transformation, with its emphasis on reducing waste and improving efficiency from the customer’s perspective, can bring huge commercial benefit to organisations that implement it well and, at the same time, offers Green credentials that benefit society as a whole. That’s worthy of further investigation, don’t you think? My microwave oven is falling to pieces. It still works, but all the plastic trim round the door has become brittle and bits are falling off every time we open it. So all praise to Sharp for their ‘Carousel II’, circa 1986 – yes, it’s nearly 24 years old (it’s even coloured beige and brown, for Heaven’s sake; when did you last see a beige and brown microwave?) and in all that time it has not skipped a beat. Actually, that’s not quite true. Something seemed to go wrong about 12 years ago. On a couple of occasions it refused to heat the food and blew a fuse. But then it picked itself up, dusted itself off, and just started working again with no intervention from anyone and it has been fine ever since. I think that is stunning reliability and I’m not naive enough to believe that we’ll get the same from its replacement; yes, after 24 years you can’t get replacement parts and, with the door seal disintegrating, it looks like the end of the line. From what I can see, the modern equivalents look prettier (beige and brown – what was I thinking?) and are 50% more powerful but most of their user interfaces are unnecessarily complicated and there are a lot of functions my family will never use. So let’s cross fingers that I don’t have to update this post for another 24 years. Update 6 Jan; someone else had a similar experience and has reinforced my worry that we won’t get anything as good, certainly not from Sharp: http://www.amazon.co.uk/review/R1AVEAZL814BHE HAPPY NEW YEAR! I hope 2010 brings you peace, happiness and success. I’m not big on resolutions, but one that I am going to make is about dear Amazon and its third party retailing arm, Amazon Marketplace. My recent experience corroborates past experience; between 1 in 2 and 1 in 3 fail to arrive, or arrive too late, or the wrong things arrive, or the product is damaged, and often you can’t get hold of the retailer to do anything about it. I’m afraid that it comes across as Amateur Hour, just the sort of thing that gives Internet shopping a bad name. Here’s just one example out of several – it was a product ordered in plenty of time for an end-of-term presentation and for which I paid extra for rapid delivery; it arrived far too late, despite leaving more than enough time, and the wooden handle had been varnished then put into its plastic bag still wet which caused the damage you can see – it should be very smooth (the raised edges of varnish were so sharp you could cut yourself on some of them).
We were even lucky to get it in such ‘good’ condition; the packaging was so poor that it had a high likelihood of the metal parts being bent in the post. For some time the supplier couldn’t be contacted because his “computer had problems and the chap who fixes it is on holiday”. Eventually he offered to send another one, then someone else associated with his business countermanded him and refused. I did get my money back eventually, but that isn’t the point. In my opinion the problem stems from the nature of Marketplace; although some of its vendors are large and reputable – or even small and reputable, I have nothing against small businesses – many of them seem to be hobby or spare-time businesses with no independent web or physical presence and little quality control. And you get the results you would expect, especially at a busy time such as Christmas. So in 2010 I’ll vote with my feet. I’ll stick with Amazon itself (which has been fine in my experience), not its Marketplace; I will go to those that deliver great customer service, and I’ll eschew those that don’t care or won’t deliver. Don’t you just hate the new self-service checkouts? The ones that “save you time” but actually take a lot longer than the normal ones and save the supermarket shed-loads of money at your expense. Sainsbury’s, Tesco and B&Q seem to be the worst offenders in my part of the world. Why they believe that it will be anything other than a disaster if the general public operate their checkouts I’m at a loss to know. Even trained operators, who do the job for 8 hours a day, have many glitches that need multiple scanning, manual bar-code number entry, or a supervisor’s help. The general public will only do the job for a few minutes a week and have no training at all, so the probability of failure is multiplied many times over. My wife tried a new Sainsbury’s self-checkout yesterday; she only had 6 items, “how hard can it be?” She couldn’t put anything else on the checkout area as she went through the process – it seemed to be weighing the goods before and after scanning to make sure she was scanning them all, so handbags and other shopping had to be scraped along the floor. For the bottle of wine she had to call a supervisor to verify she was over 18 (she’s in her mid fifties!) On two other items the system very loudly said it couldn’t read the bar-code and in each case a supervisor had to be called. For one of these even the supervisor, after several minutes of fiddling around, couldn’t sort it so she had to take everything to a different checkout with the supervisor and re-scan it all. I enjoy using new technologies and gadgets, but I now insist on going through a traditional, manned checkout because DIY checkouts are so awful. Even this isn’t the answer because the stores now punish you by restricting the number of manned checkouts, which leads to exceedingly long queues, to make you ‘prefer’ the self-checkout solution. So, let me ask what you think: This is good quality customer service, is it? This helps the customer and delivers a better shopping experience, does it? No, I don’t think so either! UPDATE: 9 December 09 – the BBC have just reported on this subject and reached similar conclusions: http://news.bbc.co.uk/1/hi/magazine/8399963.stm Zero Defects is the approach to quality that was developed and promoted by the guru Philip B. Crosby in his book ‘Quality Is Free’. Forget Six Sigma – this is ‘Infinite Sigma’! It’s a way of thinking about quality that doesn’t tolerate errors or defects and continually strives to improve processes and prevent errors so that work is always done correctly without needing repetition or rework or generating waste; this is Crosby’s philosophy of ‘right first time’. These phrases have the benefit of being unambiguous; ‘Zero Defects’ and ‘right first time’ mean exactly what they say. Think of this issue the other way round; the alternative to Zero Defects is that a certain level of defects is seen as normal or acceptable, as implied by the Acceptable Quality Limit approach; Crosby took a strong line against AQLs for precisely that reason, he saw them as a “commitment, before we start the job, that we will produce imperfect material”. Zero Defects is based on four key principles:
The key word for achieving Zero Defects is prevention, you don’t get ‘ZD’ by simply taking corrective actions to rectify existing problems, you have to stop them occurring in the first place. And, as I have mentioned before, taking preventive actions is much harder than taking corrective actions. The case for Zero Defects Zero Defects addresses the apathy that you often come across: “There will always be errors, there’s nothing you can do to prevent them”; why do we accept this statement for product manufacturing or software design but wouldn’t accept it from our surgeon as we entered the operating theatre, or in our bank accounts? Crosby explains that defects represent a cost that is often hidden (inspection, waste/scrap, rework, lost customers, etc). By eliminating defects these costs are sufficiently reduced that the savings more than pay for the quality improvement programme; hence his assertion that ‘Quality is Free’. The case against Zero Defects Zero Defects is controversial because it’s so difficult to achieve; some people claim it’s ridiculous and counter-productive to have a target of zero that will rarely be attained. They believe it will lead to excessive inspection costs and demoralised staff who keep ‘failing’. If implemented without sufficient thought it could even cause defects because of the extra stages of increasingly rigorous and expensive inspection and handling of the products. It also incurs the wrath of people who hate slogans or ‘campaigns’. Zero Defects is a difficult sell. In many regards these criticisms, although well-meant, miss the point. Crosby didn’t expect that everyone adopting Zero Defects would always achieve it, or that residual defects should be seen as failings by an individual or group. Nor did he advocate commercially unjustifiable amounts of inspection. As with many areas of quality management it’s about the philosophy and the journey you take from where you are now to being a better business, it is the “attitude of defect prevention”. When your goal is zero defects it sets a standard against which all your processes can be assessed. It’s about continually striving to work better and not being satisfied with the status quo. It’s also worth bearing in mind that he didn’t intend ‘ZD’ to always stand alone, it formed just 3 steps out of a 14 step quality improvement programme. So how do you do it? I’d love to elaborate but it’s not something that I can easily summarise in a blog. His book describes ‘how to’ in detail, so may I refer you to ‘Quality is Free: The Art of Making Quality Certain’ by Philip B. Crosby? However, you might be interested in some of his related concepts such as how to assess the real Cost Of Quality, so I’ll talk about these in future blogs; watch this space! I have written in many blogs about different ways of securing Continuous Improvement; Six Sigma, Plan-Do-Check-Act, 8D, Kaizen, and so on. The trouble is, people become too religious about their favourite technique and apply it in far more circumstances than it’s really meant for. One of my favourite quotes is “if all you have is a hammer, every problem looks like a nail”. So you should use the right tool for the job, not just the tool that you have to hand. (I can still remember the arguments when my father used to catch my mother levering lids off tins in the kitchen with his sharpest wood chisel.) Here’s an excellent blog article by American quality professional Jim Wells that espouses the ‘horses for courses’ argument: http://qualitypractice.blogspot.com/2009/01/six-sigma-or-not-to-six-sigma-that-is.html As Jim says “problem solving requires a good understanding of the different methods in the toolbox so that good decisions can be made about what to use in different situations” Well put, sir! |
Welcome to my blog, which I hope you'll find to be an interesting mixture of real-world experience, ideas, comments and observations.
Tom Gaskell
I've worked in industry as a consultant, manager and quality trouble-shooter for most of my career.
After spending 14 years in a multi-national consulting organisation and 10 years working in telecomms design and manufacturing start-ups, I set up the Cambridge (UK)-based quality, manufacturing and business consultancy Primilis (http://www.primilis.com) in 2006. |
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