Six Sigma – Definition and its Origin

Six Sigma is a data-based methodology to improve performance by reducing variability. It requires thorough understanding of product and process knowledge and is completely driven by customer expectations.

In other words, it is a methodology to achieve 3.4 defects per million opportunities. It can also be used to bring breakthrough improvements in the process. It focuses on the bottom-line and is a proven methodology for problem solving.

Goals of Six Sigma

• To reduce variation
• To reduce defects /rework
• To improve yield /productivity
• To enhance customer satisfaction
• To improve the bottom-line
• To improve top-line
• Shortening cycle-time

Sigma Level Vs Number of Defects

Evolution of Six Sigma

The need for process improvements and a continuous improvement methodology like Six Sigma came into existence only due to

• rising customer expectations in terms of quality, delivery and cost,
• global competition - Japanese and Chinese threats,
• proven technique for quantum jumps in business results.

In the year 1980, Motorola started facing survival problems due fierce competition from Japanese companies. The CEO of Motorola - Bob Galvin was determined to overcome the competition. He challenged his organization to achieve a ten-fold improvement in performance over a period of five years. To achieve the same, strong emphasis was given to training of employees and also performing global benchmarking.

Bill Smith was a veteran engineer in Motorola and he wrote a research paper on product quality and its performance after delivery to customer. In his report he discovered that the products with fewer non-conformities (high quality) were the ones that performed well after delivery to the customer. It was accepted by everyone but the challenge that came in front of Motorola executives was to develop a solution to tackle this problem.

Mikel Harry having a doctorate from Arizona University worked with Bill Smith in developing a four-phase problem solving approach - Measure, Analyze, Improve and Control. A few years later Bob Galvin launched a long-term quality program called “The Six Sigma Quality Program” in Motorola.

Looking at the success of Motorola, many companies like Texas Instruments, Allied Signal etc started using Six Sigma methodology to bring organization-wide improvements.

In 1990’s Jack Welch launched Six Sigma in GE in a big way. He implemented Six Sigma in all areas and ensured that the entire organization participates in the initiative. He changed the performance incentives and made them based on individual’s ability and enthusiasm to take part in Six Sigma initiatives. He transformed GE to a state where Six Sigma had become the culture of the organization and not just a methodology for brining organization-wide improvements.