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The industrial age was approaching its second century when a young engineer named Walter A. Shewhart altered the course of industrial history by bringing together the disciplines of statistics, engineering, and economics. He referred to his greatest achievement, the invention of the process control chart, as “the formu-lation of a scientific basis for securing economic control.” The Shewhart control chart is now sometimes referred to as a process behavior chart.

Shewhart wanted statistical theory to serve the needs of industry. He exhib-ited the restlessness of one looking for a better way. A man of science who patiently developed his and others’ ideas, he was an astute observer of the world of science and technology. While the literature of the day discussed the stochastic nature of both biological and technical systems, and spoke of the possibility of applying sta-tistical methodology to these systems, Shewhart actually showed how it was to be done. In that respect, the field of quality control can claim a genuine pioneer in Shewhart. His book Economic Control of Quality of Manufactured Product, published in 1931, is regarded as a complete and thorough exposition of the basic principles of quality control.

Called upon frequently as a consultant, Shewhart served the War Department, the United Nations, the government of India, and others. He was active with the National Research Council and the International Statistical Institute. He was a fellow of numerous societies and in 1947 became the first honorary member of the American Society for Quality. Many consider the Shewhart Medal, given for out-standing technical contributions to the quality profession, to be by far the most prestigious award the American Society for Quality offers.

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W. Edwards Deming and Joseph M. Juran

The impact of the Bell Telephone System on the quality profession is almost beyond belief. Shewhart, Edwards, Juran, and Deming all worked for and learned from the Bell System in one way or another. Edwards and Shewhart retired as Bell System employees. Both Juran and Deming went on from the Bell System to become world-famous consultants and authors.

Deming became the best-known quality expert in the United States. He deliv-ered his message on quality not only throughout the United States but also around the world. In recognition of his valuable contribution to Japan’s post-war recovery, the Union of Japanese Scientists and Engineers established an annual award for quality achievement called the Deming Prize.

Deming (1982) emphasized that the keys to quality are in management’s hands—85 percent of quality problems are due to the system and only 15 percent are due to employees. The heart of his quality strategy is the use of statistical qual-ity control to identify special causes (erratic, unpredictable) and common causes (systemic) of variation. Statistical tools provide a common language for employ-ees throughout a company and permit quality control efforts to be widely dif-fused. Each employee assumes considerable responsibility for the quality of his or her own work. Those in traditional quality control functions are then able to take more proactive roles in the quality improvement effort.

Deming introduced statistical quality control to the Japanese in the early 1950s when Japan was recovering from World War II and trying to overcome a reputa-tion for shoddy workmanship. Deming’s guidance was instrumental in transform-ing “made in Japan” from a liability to an asset. Demtransform-ing asserted that there was no point in exhorting employees to produce higher-quality work because the changes needed to improve quality were almost always outside of the workers’ control, such as having the right tools, training, and materials. Instead, management had to accept responsibility for quality. Based on his experience, Deming developed a 14-point set of requirements called Deming’s 14 points, shown in Figure 1.1. He also described seven deadly diseases of the workplace, including emphasis on short-term profits, use of personnel performance evaluations, which he labeled “management by fear,” and mobility of management (that is, management as a profession inde-pendent of the product/service or commitment to the organization).

Juran, like Deming, built his quality reputation in America and then took his expertise to Japan in the 1950s. The two complemented each other well in Japan, as Deming showed the use of statistical tools and Juran taught the tech-niques of managing for quality. Juran originated the concept of “the vital few”

and the “useful (originally ‘trivial’) many,” which he labeled the Pareto princi-ple, now enshrined in the well-known Pareto diagram. An economist, Vilfredo Pareto, had noticed the phenomenon but it was Juran who applied it to quality improvement.

Juran recognized that to improve quality requires a completely different approach from what is needed to maintain existing quality. He demonstrated this idea in his book Managerial Breakthrough, first published in 1964, and later con-densed his ideas into the Juran trilogy:

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1. Quality control: monitoring techniques to correct sporadic problems (analogous to special causes)

2. Quality improvement: a breakthrough sequence to solve chronic problems (analogous to common causes)

3. Quality planning: an annual quality program to institutionalize managerial control and review

Juran served the quality profession well when in 1951 he created the monumental Juran’s Quality Handbook, now in its fifth edition. Juran’s contributions are extensive and varied. He defined quality as “fitness for use by the customer.” He emphasized

1. Create consistency of purpose toward improvement of products and services, with a plan to become competitive and to stay in business. Decide to whom top management is responsible.

2. Adopt the new philosophy. We are in a new economic age. We can no longer live with commonly accepted levels of delays, mistakes, defective materials, and defective workmanship.

3. Cease dependence on mass inspection. Require instead statistical evidence that quality is built-in to eliminate need for inspection. Purchasing managers have a new job and must learn it.

4. End the practice of awarding business on the basis of price tag. Instead, depend on meaningful measures of quality, along with price. Eliminate suppliers who cannot qualify with statistical evidence of quality.

5. Find problems. It is management’s job to work continually on the system (design, incoming materials, composition of material, maintenance, improvement of machines, training, supervision, retraining).

6. Institute modern methods of training on the job.

7. Institute modern methods of supervision of production workers. The responsibility of foremen must be changed from sheer numbers to quality. Improvement of quality will automatically improve productivity. Management must prepare to take immediate actions on reports from foremen concerning barriers such as inherited defects, machines not maintained, poor tools, fuzzy operation definitions.

8. Drive out fear, so that everyone may work effectively for the company.

9. Break down barriers between departments. People in research, design, sales, and production must work as a team, to foresee problems of production that may be encountered with various materials and specifications.

10. Eliminate numerical goals, posters, and slogans for the workforce, asking for new levels of productivity without providing methods.

11. Eliminate work standards that prescribe numerical quotas.

12. Remove barriers that stand between the hourly worker and his right to pride of workmanship.

13. Institute a vigorous program of education and retraining.

14. Create a structure in top management that will push every day on the above 13 points.

Figure 1.1 Deming’s 14 points.

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the need for top managers to become personally involved in order for a quality effort to be successful and for middle and lower-level managers to learn the lan-guage and thinking of top management—money, for example—in order to secure their involvement. Juran’s universal process for quality improvement requires study-ing symptoms, diagnosstudy-ing causes, and applystudy-ing remedies. He repeatedly empha-sized that major improvement could be achieved only on a project-by-project basis.

The basis for selecting projects was return on investment, now a major component of Six Sigma.