In this lesson, we will talk about quality control and the different milestones and individuals who are responsible for the quality movement. We'll look at some of the awards that are given out for quality and talk a little bit about some of the standards that are used for quality management. Now it's seldom that one can point to one individual who started a whole movement. But in our case, the whole quality movement seems to have started with Walter Shewart. Now Walter Shewart was a physicist and he was working for Western Electric Company, which was a contractor to Bell Telephone, and Western Electric Company had a very large manufacturing facility called the Hawthorne Plant in Cicero, Illinois. While he was working there, Shewart came up with this idea of statistical control charts. Now an example of a statistical control chart is shown in the figure on this slide and this is a particular kind of control chart called a P-Chart. Shewart came up with his control charts in 1924 and his reason for doing this was to help the line workers understand the importance of variability in measurements as they made telephones and as they measured characteristics of these telephones. And much of what we are going to talk about in this module on quality management is based on what Shewart came up with his ideas. Shewart was also responsible for creating what is called the Plan-Do-Study-Act cycle. Now the Plan-Do-Study-Act cycle was later modified to Plan-Do-Check-Act when it went to Japan and there was a little bit of resistance of changing study to check because what Shewart wanted with study was to look at many different alternatives and understand how the actions were actually affecting the quality that was being studied whereas the check became more to ensure that what was being planned or what was, the change that was being proposed, was actually resulting in the desired characteristics. Unfortunately though, a lot of Shewart's ideas by 1941 had fallen out of popularity and were not even being used in the Hawthorne plant because the focus was more on creating more production and lowering cost and quality was not a main concern. Walter Shewart was at the Hawthorne Plant and at the Hawthorne Plant he interacted with two other stalwarts of the quality management movement. One was W. Edwards Deming and the other one was Joseph Juran. Both these individuals saw the ideas that Walter Shewart had come up with. Now Walter Shewart was a brilliant man, but as it happens often with brilliant people, they're not the best at explaining their ideas. In fact, Deming is quoted as saying that Shewart would come up with an idea and then find the most complicated way to explain that idea. And so what Deming and Juran did is they started looking at Shewart's ideas and figuring out how best to convince other people to use these ideas. So that brings us to our second pioneer, W. Edwards Deming. W. Edwards Deming is responsible for popularizing a lot of Shewart's ideas. Now this makes it seem like Deming did not have any new ideas, but Deming was a statistician as well and he came up with the sampling techniques that were used by the Census Bureau in 1940. Deming was also the person who convinced the military to train people in the ideas of quality. Because of the lack of reception for his ideas in the U.S., Deming decided to try and see if those ideas would work in Japan. He had been invited to give a set of talks; in a series of eight talks right after the war, Deming talked to a number of Japanese executives and mid-level managers about the notion of quality and about statistical quality control. Many of Deming's ideas were adopted by the Japanese and, in fact, Deming is considered the father of Japan's revival post-World War II. In fact, because of his influence, the Japanese created a prize called the Deming Prize which was given to companies which excelled in quality management. Another person who was influenced by William Shewart was Joseph Juran. Juran came up with a number of different ways to try and make quality more meaningful to main line managers. The first thing that he realized was the use of something called the Pareto principle. Pareto was an Italian economist who came up with this notion that 80% of time is spent on 20% of activities, or 80% of the wealth is being held by 20% of the people. Juran decided to apply Pareto's principle to quality issues pointing out that a small number of quality issues take up most of the time and most of the cost. Now Juran is also known for his Juran Trilogy. Now the Juran Trilogy essentially says that quality has to follow three different phases. The first is the planning phase in which what you ought to be looking at are what are the customer needs and what are the broad goals that one wants to set for quality? The second is the control phase where one's quality standards are established; you want to evaluate performance against your standards, compare it against goals to see how one is performing against what one intended. Then lastly, there's an improvement phase in which one looks at creating an infrastructure that allows for constant study and constant improvement of quality. In this phase, one would identify projects that one must do to improve quality or improve processes. Now much of this would look similar to some of the ideas that one talks about when one talks about operations improvements, when one talks about Lean Management, when one talks about Six Sigma. The reason for this is that a lot of these ideas of Lean Management and Six Sigma, etc., which are continuous improvement ideas, were all co-developed around the same time. Lastly, Juran is known for emphasizing the cost of quality. Juran talks about the costs of quality, the costs associated with components failing, so the failure costs. Then he talks about the appraisal costs. Appraisal costs are the costs of actually measuring things and evaluating whether things are within our tolerance, etc. Then he talks about prevention costs, and these are the costs associated with making sure that machines are maintained, that tools are sharpened, etc., so that quality can be achieved. So this notion of looking at quality not just as a final product and looking at whether it fails in the field or not, but working it back through the entire process of making that particular part and figuring out where costs associated with quality lie. That is part of Juran's legacy. Around this time when Shewart, Deming, and Juran were popularizing many of the ideas of statistical process control and the importance of cost, there were people in Japan who, having heard Deming, were now looking at improving quality themselves. A pioneer from Japan was Professor Kaoru Ishikawa. He was a professor in University of Tokyo and he's most famous for what is known as the Ishikawa Diagram. This is also sometimes known as a Fishbone diagram and the Fishbone diagram is often used to show cause and effect when one looks at different modes of failure for any device or a system. Professor Ishikawa was the pioneer of quality circles. He started this notion of quality circles in Japanese companies wherein workers would form quality circles, which would be places where they could discuss quality issues, come up with solutions, etc. Lastly, he came up with this notion that quality was not simply inspecting the parts of the processes, but it was a company-wide activity and that everyone in the company had responsibility for quality. On the U.S. side, yet another person who had a major contribution to the quality management movement was Armand Fiegenbaum. Armand Fiegenbaum was a Operations Manager at General Electric. He came up with this notion of what is called total quality control. Total quality control evolved into what we now call total quality management. The notion of total quality control or total quality management is the fact that quality is an organization-wide effort, and the only way to improve quality is if one thinks of it from an organization point of view and not from an individual, small process, or machining operation point of view. Fiegenbaum was one of the first people to articulate this notion that when one looks at a manufacturing plant, there is enough waste in the plant that the waste itself could be thought of as being another whole manufacturing plant. This is what he called the notion of the hidden plant. The idea here is to highlight the fact that there is tremendous amount of waste that occurs in manufacturing operations. We could also extend that now to service operations. Reduction of this waste or removal of this hidden plant should be one of the goals of any continuous improvement activity. Finally, Fiegenbaum looked at quality costs. One of the things he realized is that many of the people who made high-level decisions did not understand what the costs of quality were. So, when they looked at their ledgers, for example, and when they looked at their accounts, for example, they did not see anywhere where the costs of quality were identified. So, Fiegenbaum spent a lot of effort trying to show what different costs that managers typically looked at could be attributed to quality or lack of quality. So, that became one of his big contributions to the quality movement. Then, we come to Genichi Taguchi. Now, Taguchi was influenced by the work of statistician Fisher. So Taguchi, one of his contributions, was what's called the Taguchi Method. What Taguchi articulated was the fact that there are several points in the design process where quality can be impacted. The first point where quality can be impacted is when one is specifying the system. By system, it could be the system that makes parts, it could be the design of the components, or the product itself that one is interested in. The next point at which quality gets affected is the specification of parameters of this system. So when one talks about specifications of the parameters of the system, if one looks at a part, one could think about the dimensions of that particular part. Then, the last part where quality gets impacted is the specification of tolerances. So, for example, if I tell you that a part has to have a diameter of six inches, I might need to say that I need to have a tolerance around the six inches. So, I might say, six inches plus or minus 0.1 inches. The plus/minus 0.1 inches is then the tolerance. Specifying a tolerance will affect quality. For example, if I specify too tight a tolerance, then it may not be possible for me to produce parts which will be within the tolerance, and so I will create defective parts. If the tolerance is too wide, the part may not function properly in the equipment in which it is supposed to be put. That may cause failures of the equipment, leading to further costs. So, there are three points at which one can influence the costs associated with quality according to Taguchi. Now, the other thing Taguchi brought to the forefront was this idea that when one thinks about quality, quality is not a zero-one decision. The normal tendency is to think of a part as either being defective or not defective. What Taguchi articulated was that because there is a certain tolerance within which the part can function, what matters then is where within that tolerance does the measurement of that part lie? So, if one is exactly at the nominal value, then the cost is going to be zero. But as one goes further and further away from the nominal value of the part, then the costs associated with qualities of that part keep increasing. They increase in a parabolic fashion, which means they increase rapidly as one goes away from the nominal value. Finally, Taguchi is also famous for his contributions to design of experiments. Some of his contributions are somewhat controversial because of theoretical underpinnings of his ideas, but they are important because Taguchi brought out this notion that the environment in which experiments are performed can often have significant impact on the results of those experiments. These are some of the main stalwarts of the quality movement. Now, obviously, there were other people who either popularized, implemented, or added bits and pieces to the whole quality management movement, but the broad and big ideas came from some of these people.
