What Are QFD and Six Sigma?

This chapter is from the book

Quality Function Deployment and Six Sigma, Second Edition: A QFD Handbook, 2nd Edition

Learn More Buy

This chapter is from the book

This chapter is from the book 

Quality Function Deployment and Six Sigma, Second Edition: A QFD Handbook, 2nd Edition

Learn More Buy

1.3 History of QFD and Six Sigma

1.3.1 Origins of QFD

The people identified in this chronology have made special efforts in the best interests of U.S. industry. They could have kept QFD and Six Sigma as proprietary secrets, not to be shared with the competition. Instead, they shared their experiences with others, including their competitors, and everyone has gained.

QFD became widely known in the United States through the efforts of Don Clausing, of Xerox and later MIT, and Bob King of GOAL/QPC. These two worked independently, and likely first came into contact in October 1985, when Clausing presented QFD at a GOAL/QPC conference in Massachusetts. By that time, both men had already made significant contributions toward promoting QFD.

The Japanese characters for QFD are:

• (hinshitsu), meaning "quality,""features,""attributes," or "qualities"¹⁴
• (kino), meaning "function" or "mechanization"¹⁵
• (tenkai), meaning "deployment,""diffusion,""development," or "evolution"

Any of the English words could have been chosen by early translators of Japanese articles. It's little more than a matter of chance that QFD is not called Feature Mechanization Diffusion today. In the early days, when Lou Cohen explained QFD to audiences, he attempted to rename it Structured Planning, or Quality Feature Deployment, in the hope that people would be able to tell from its name what QFD was all about. For better or for worse, "Quality Function Deployment" has stuck in the United States, and no alternative name is likely to survive. None of the thirty-two possible combinations of English equivalents really denotes what QFD actually is. We must be content with a name for the process which is not that self-explanatory.

1.3.2 Early History of QFD in Japan

Yoji Akao¹⁶ cites the rapid growth of the Japanese automobile industry in the 1960s as a driving force behind the development of QFD. With all the new product-development drives in the Japanese auto industry, people there recognized the need for design quality and that existing QC process charts confirmed quality only after manufacturing had begun. Mr. Akao's work with Kiyotaka Oshiumi of Bridgestone led to "Hinshitsu Tenkai" or "Quality Deployment," which was taken to various companies with little public attention. The approach was later modified in 1972 at the Kobe Shipyards of Mitsubishi Heavy Industry to systematically relate customer needs to functions and the quality or substitute quality characteristics. The first book on the topic, Quality Function Deployment by Akao and Mizuno, was published by JUSE Press in 1978.¹⁷

1.3.3 History of QFD in the USA

In 1983, the first article on QFD by Akao appeared in Quality Progress by ASQC,¹⁸ and from there things spread quickly. Don Clausing first learned about QFD in March 1984, during a two-week trip to Fuji-Xerox Corporation, a Xerox partner in Japan. Clausing, a Xerox employee at that time, had already become interested in the Robust Design methods of Dr. Genichi Taguchi, who was a consultant to Fuji-Xerox. While in Japan, Clausing met another consultant to Fuji-Xerox, a Dr. Makabe of the Tokyo Institute of Technology.

At an evening meeting, Dr. Makabe briefly showed Clausing a number of his papers on product reliability. "After fifteen minutes," relates Clausing, "Dr. Makabe brushed the papers aside and said, 'Now let me show you something really important!' Makabe then explained QFD to me. I saw it as a fundamental tool that could provide cohesion and communication across functions during product development, and I became very excited about it."

In the summer of that same year, Larry Sullivan of Ford Motor Company organized an internal company seminar. Clausing was invited to present QFD. Sullivan quickly grasped the importance of the QFD concept and began promoting it at Ford.

Clausing continued to promote QFD, Taguchi's methods, and Stuart Pugh's concept-selection process at conferences and seminars. When Clausing joined the faculty at MIT, he developed a semester-length graduate course that unified these methods along with other concepts into a system for product development that eventually became called "Total Quality Development." Many of his students, already senior managers and engineers at large U.S. companies, returned to their jobs and spread his concepts to their coworkers.

In June 1987, Bernie Avishai, associate editor of Harvard Business Review, asked Don Clausing to write an article on QFD. Clausing felt that the paper should be given a marketing perspective, and he invited John Hauser to coauthor it. Hauser had become intrigued with QFD after learning about it from a visit to Ford. The article, published in the May–June 1988 issue of the Harvard Business Review, has become one of the publication's most frequently requested reprints. That article probably increased QFD's popularity in the United States more than any other single publication or event.

Larry Sullivan founded the Ford Supplier Institute. This was a Ford Motor Company organization aimed at helping Ford's suppliers improve the quality of the components they developed for Ford. Sullivan and others at Ford gained a detailed understanding of QFD by working with Dr. Shigeru Mizuno and Mr. Akashi Fukahara from Japan. Eventually Ford came to require its suppliers to use QFD as part of their development process, and the Ford Supplier Institute provided training in QFD (along with other topics) to these suppliers.

The Ford Supplier Institute eventually became an independent nonprofit organization, the American Supplier Institute (ASI). ASI has become a major training and consulting organization for QFD. It has trained thousands of people in the subject.

Bob King, founder and executive director of GOAL/QPC, first learned of QFD from Henry Klein of Black and Decker. Klein had attended a presentation on QFD given by Yoji Akao and others in Chicago in November 1983. The following month, Klein attended a GOAL/QPC course on another TQM topic, where he told King about this presentation and about QFD. King began offering courses on QFD starting in March 1984. In the summer of that year, King learned more details about QFD from a copy of a 1978 book by Akao and Mizuno, Facilitating and Training in Quality Function Deployment. In the fall of 1984, King began offering a three-day course on QFD, based on the understanding of the tool he had gained from the Akao and Mizuno book. In November 1985, King traveled to Japan and met with Akao to "ask him all the questions he couldn't answer." Akao provided King with his course notes on QFD, and he gave GOAL/QPC permission to translate the notes and use them in his GOAL/QPC courses.

Based on these notes, GOAL/QPC offered its first five-day course on QFD in February 1986. Lou Cohen attended that course and learned about QFD there for the first time.

At the invitation of Bob King, Akao came to Massachusetts and conducted a workshop on QFD in Japanese with simultaneous translation into English. Akao conducted a second workshop in June 1986, also under the auspices of GOAL/QPC. For this second workshop, GOAL/QPC translated a series of papers on QFD, including several case studies. This translation was later published in book form.¹⁹ Eventually this collection of QFD papers became what remains the standard advanced book on QFD.

In 1987, GOAL/QPC published the first full-length book on QFD in the United States: Better Designs in Half the Time, by Bob King.²⁰ In this book, King described QFD as a "matrix of matrices" (see Chapter 18). King relates that in June 1990, Cha Nakui, a student of Akao's and later an employee in Akao's consulting company, "comes to work for GOAL/QPC and corrects flow of QFD charts." Among Nakui's contributions to our understanding of QFD is his explanation of the Voice of the Customer Table (see Chapter 5).

I first saw QFD while at AlliedSignal, now Honeywell, circa 1990. Early examples at that time included Toyota Motors' QFD processes. At the same time, Value Engineering was being taught at AlliedSignal, along with Robust Design methods from the American Supplier Institute. John Fox's seminal work, Quality Through Design: Key to Successful Product Delivery, was published in 1993, and included aspects of Design Process Flow, QFD, Design for Manufacture, and Critical Parameter Management, among many other methods. This work is one of the earliest to set the stage for Design for Six Sigma (DFSS) and QFD.

Other important early publications in the United States include

• "Quality Function Deployment and CWQC in Japan," by Professors Masao Kogure and Yoji Akao, Tamagawa University, published in Quality Progress magazine, October 1983
• "Quality Function Deployment," by Larry Sullivan, published in Quality Progress magazine, June 1986
• Articles on QFD by Bob King and Lou Cohen in the spring and summer 1988 editions of the National Productivity Review
• A series of articles on QFD in the June 1988 issue of Quality Progress magazine
• A course manual on QFD to supplement ASI's three-day QFD course
• Annual Proceedings of QFD symposia held in Novi, Michigan, starting in 1989

QFD software packages first became available in the United States around 1989. The most widely known package was developed by International TechneGroup Incorporated. Some organizations heavily committed to QFD, such as Ford Motor Company, have developed their own QFD software packages.

Early adapters of QFD in the United States included Ford Motor Company, Digital Equipment Corporation, Procter and Gamble, and 3M Corporation. Many other companies have used QFD, and the tool continues to grow in popularity. More than fifty papers were presented at the Sixth Symposium on Quality Function Deployment in 1994. Only a few of these papers were not case studies. The majority of companies using QFD are reluctant to present their case studies publicly, since they don't want to reveal their strategic product planning. Therefore, it is likely that the fifty papers presented at the QFD Symposium represent just the tip of the iceberg in terms of QFD implementation.

Figure 1-13 identifies many key events in the development of QFD, both in Japan and the United States. In some cases, where exact dates are not known, approximate months or years have been provided.

Figure 1-13. History of QFD in the United States²¹

1.3.4 History of QFD with Six Sigma

Dr. Stephen Zinkgraf²² observes that at Motorola in the late 1980s, QFD's use was frequently at the front end of designing new products. The focus was initially on two-way matrices, until Fernando Reyes used QFD in a very innovative fashion—to develop the strategic plan for manufacturing automotive electronic applications based on customer requirements.

In 1995, Zinkgraf was leading Six Sigma Deployment at the AlliedSignal Engineered Materials Sector, and was putting together the Six Sigma operations roadmap. He concluded that Six Sigma should be based on understanding the interaction between process inputs (Xs) and process outputs (Ys). Since the Ys were to reflect satisfying customer needs, it seemed that a two-way matrix mapping the process inputs generated by the process map focused on inputs and outputs to process requirements. It fit perfectly into the final roadmap. The process map generated the inputs to the Cause & Effect matrix. The C&E Matrix focused the FMEA on only the important inputs, thereby shortening and focusing the FMEA process. The roadmap—including the process map, the C&E Matrix, and the FMEA—opened the door to the Analysis phase of MAIC. The C&E Matrix, when done properly, yielded a process focus that really hadn't existed before, outside of the archaic fishbone diagram. The C&E Matrix is essentially the result of quantitative generation of multiple fishbone diagrams quickly. The limitation of the fishbone diagram had been that it was not focused on process inputs and allowed analysis of only one output at a time. With multiple outputs, it was not possible to aggregate the results into a single plan of action.

In 1998, I gave a talk entitled "QFD with a Six Sigma Twist" at an Annual Black Belt conference. In this talk, I commented that the QFD applications I had seen previously needed more of a VOC emphasis on the front end with FMEA, as well as some sampling strategies to better detail what they really needed. I also commented that more-detailed data and analysis on the linkages between matrices could be obtained with process maps and other Six Sigma tools, to enable users to truly understand the Y = f(x) relationships implied when connecting Hows to Whats. Additionally, I commented on the "How wells"—that true process capabilities needed to be determined in scoring what was possible. I received positive feedback on turning what was then some large variation of QFD application into a flow map that could be followed. That flow map is illustrated in Figure 1-14.

Figure 1-14 A Historical Flow Map of QFD and Six Sigma Tools from 1997