By Xavier Perrin (xperrin@xp-consulting.fr)
For some time, I noticed a new trend on LinkedIn: the proliferation of cards intended to explain, with pretty pictures, professional best practices. With the systematic mention (injunction?) at the bottom of the card: "please like, share, subscribe"! This leads me to believe that the primary aim of these cards isn't to enrich the readers' knowledge, but instead to enhance the authors' reputation. However, reading these cards sometimes reveals the superficial knowledge of authors who obviously have little experience with the concepts they describe. Such cards are very effective for their primary purpose as they do indeed allow for a lot of "likes" and comments, the most common being "very informative!". The other day, it wasn't the card itself that annoyed me, but a comment from a reader who thought he was enriching the subject but was putting forward a big stupidity... which in turn was commented on by an enthusiastic "absolutely" from the author! The card in question briefly described the PDCA (Plan-Do-Check-Act) cycle as a problem-solving tool, which is not wrong but reductive. The reader's comment praised the merits of the PDCA cycle in restoring "common sense" in our businesses. The silliness of the comment, validated by the author, is that the PDCA cycle (Also known as the PDCA circle) was proposed as a bulwark against actions based on common sense alone. Indeed, when it comes to solving a problem, it's because common-sense solutions don't work. Common sense means applying what you know. But when you don't know what to do, you have to learn. That's what the PDCA cycle is all about.
Where does this method come from? Walter A. Shewhart (1891 – 1967) was an American mathematician, who devoted most of his career to apply statistics to assure the quality of products and processes of The Bell Laboratories where he worked. To ensure that solutions to quality problems come from methodical thinking rather than preconceived ideas and "common sense", he proposed a five-step routine: Plan, Do, Study, Act (PDSA) for conducting scientific reasoning. However, it is William Edwards Deming (1900 – 1993) who is credited with disseminating this method. W.E. Deming was also a statistician and was aware of the work of W.A. Shewhart. In 1947, the US government sent him to Tokyo to help the Allies improve sampling techniques. His stay in Japan gives him the opportunity to give lectures and seminars organized by the Japanese Union of Scientists and Engineers (JUSE) which had just been formed to help Japanese manufacturer to rebuild their industry after the war. It was during these conferences that he popularized the PDSA cycle, which had been renamed PDCA meanwhile, where the S of "Study" was replaced by the C of "Check". Among the attentive participants were Eiji Toyoda and Taichi Ohno, chairman and production manager, respectively, at Toyota Motor Corporation. It was a revelation to them, and they decided to systematically use the PDCA cycle in their company with the success we know. Mike Rother, in "Toyota kata"(1), describes well how the PDCA cycle is the basis of the management of Toyota, from the chairman to the line workers. And he clearly explains how to use it (Of course, this is a book with hundreds of pages, and it requires more effort to read it than a card on LinkedIn!) In his book, "The New Economics for Industry, Government, Education"(2), W.E. Deming writes: "The Shewhart Cycle is a tool for learning something and for improving a product or process". It's the opposite of common sense: common sense means acting on what we know. But it is always risky to act on what we don't know! This is why we need to learn before acting (Letter A of PDCA). Plan is the step where we describe the problem, why it is important to solve it, and the new condition we want to create. It is also about gathering all the existing knowledge that will help in finding the causes of the problem and imagining solutions to eliminate them. It is the most important step. Albert Einstein, who was quite successful in solving some nice problems, would have said: "If I had an hour to solve a problem, I would have spent 55 minutes defining the problem and only 5 minutes finding a solution". Do is about implementing the proposed solutions. The goal of the Check step is to analyze the results obtained from the implementation of the solutions in order to verify their effectiveness. The progress of the PDC steps leads to the acquisition of new knowledge that will allow us, either to go back to the previous steps (Adjust) if the results are not satisfactory, or to define a new way of acting (Act) if the new knowledge allows satisfactory results.
In addition to its 4 stages, the PDCA circle also embodies the idea of continuous improvement, so dear to W.E. Deming. Indeed, the famous circle is often referred to as the “Deming wheel”. But the function of a wheel is to turn! In other words, once we have acquired the new knowledge that has enabled us to improve quality or any other performance factor, we return to step P with the question: how can we achieve a higher level of performance? And so on, until we reach excellence. This is the essence of continuous improvement.
Another bad habit creates confusion about the true nature of the PDCA cycle. Sometimes we push our students to use the PDCA cycle (Or DMAIC which is a similar approach to scientific thinking used in the Six Sigma method which aims to reduce the variability of processes) as a structure for their reports or internship dissertation. But, if the issue is, for example, "Improve inventory record accuracy by implementing barcode readers", it is not a question of creating knowledge for solving a problem. Here the solution is well known: we consider (by common sense?) that the solution has been found and that it is necessary to implement barcode readers. It is not about solving a problem but about managing a project, and there are well-known and very effective techniques for doing this. In the previous example, when I encouraged the student to use the PDCA circle to solve the problem "how to improve inventory record accuracy", the 'P' step revealed that the "barcode readers" solution did not address the identified causes. Encouraging students to misuse the PDCA cycle contributes to its lack of understanding within organizations.
I just mentioned that the DMAIC method is an adaptation of the PDCA circle. Other methods have been adapted from it, such as 8D and 9S (the latter being used mainly in the aeronautical industry). I don't intend to describe all these methods here, as there are many resources available on the subject (not only cards on LinkedIn!). However, as with the PDCA circle, they are only effective if they are used wisely.
Unfortunately, learning the intricacies of the PDCA cycle takes more time than reading a pretty card. We need to understand the thinking of those who invented it and why they invented it. Moreover, it is necessary to practice, first with the help of a mentor, because common sense will inevitably lead us to skip the steps and not learn anything.
(1) Mike Rother, "Toyota Kata, Mc Graw Hill 2010
(2) W. Edwards Deming, "The New Economics for Industry, Government, Education" 2nd Edition, MIT, 1994