Sigma Level Vs Number of Defects Sigma Level | Number of defects per Million | 2 Sigma | 308537 | 3 Sigma | 66807 | 4 Sigma | 6210 | 5 Sigma | 233 | 6 Sigma | 3.4 |
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