Evolution of Six Sigma

In this chapter, we will review the Six Sigma timeline to get an understanding of the evolution of Six Sigma over time. The important Six Sigma term standard deviation was defined in the 19th century, but if we go backward in time to the late 1800s we have Frederick Taylor and Tayloristic thinking. Taylor’s economic theory, the division of labor, gave rise to a lot of the things that we would call Six Sigma today. In the 1920s we had folks like Henry Ford and Walter Shewhart, George Box and others that were doing development around Six Sigma as we would recognize it today. As you move into the 1940s, there was a big push by the US government to support military manufacturing. This is where the notion of statistical process control really came to the forefront. These included the early teachings of statistician Walter Shewhart. And then after World War II, we had Dr. D Edwards Deming and Dr. Joseph Juran. Their work in Japan led to the development of quality as a competitive differentiator for the Japanese. It was during this time that the Japan Union of Scientist and Engineers was born and began to create some of the foundations for what we later adopted as total quality management, or TQM. As we moved into the 1970s and early 80s, it was Michael Harry and others working with Motorola, and General Electric that crafted and branded the concept of Six Sigma as a term to bundle these methods together. This has all led to the modern day, and Six Sigma being applied in many different industries.

Now we will cover some key improvement concepts that have been developed over the years. Back in the early 1920s there was the Plan, Do, Check, Act cycle. Then as we moved into the 1960s and 70s this led to statistical process control and the formation of the Japan Union of Scientists and Engineers. Then the United States began adopting and embracing total quality management, or TQM in the 1980s. In that same time frame is when quality circles developed by the Japanese began to be well understood. Moving into the late 80s and early 90s, we had the integration of ISO9000 with total quality management and the development of the Baldrige criteria for performance excellence. Now we will explore the Plan, Do, Check, Act, or PDCA cycle in more depth. It generally starts with a plan of understanding. What is it that we want to change and why are we changing it? Then we take action to actually do it followed by the all important check step. Sometimes this is actually referred to a study. But it’s validating to determine if what we did actually accomplished what we planned. If we don’t pass the test in the Check step we would initiate another cycle of PDCA. So PDCA is a cycle of continuous improvement to improve processes.

We may implement the PDCA cycle along with statistical process control, where we track data and determine if the number of defects is acceptable or not. Continuing with the theme of total quality management, this involved in the direct response to the increasing competitiveness of Japan in the 70s and 80s, and taking business away from the United States. This was a United States based initiative around branding total quality, which is a precursor to what we would call Six Sigma today. During the 1990’s we saw the ISO9000 standards being developed. Quality focused organizations incorporated ISO9000 standards in order to win recognition and credibility within their industries and with customers. The Baldridge criteria is another set of standards for performance excellence. The criteria includes seven important elements. The elements are Leadership, Strategic Planning, Customer and Market Focus, Measurement, Analysis and Knowledge management. Human Resource Focus, Process Management, and finally, controlling results to create repeatability and capability within the organization. The evolution of Six Sigma as we know it today is largely credited to the work done at Motorola and at General Electric. Michael Harry and many other very prominent quality leaders were involved with that. Their early work led to the worldwide acceptance of Six Sigma as a practical set of methodologies, to improve results for any kind of business.