Statistics for Six Sigma Made Easy! Revised and Expanded Second Edition, 2nd Edition

INTRODUCTION

THE HISTORY OF SIX SIGMA

Motorola developed much of the Six Sigma methodology in the 1980s. The company was putting large numbers of transistors into its electronic devices, and every transistor had to work or the device failed. Therefore, Motorola decided that it needed a tighter quality criterion based on defects per million rather than the traditional defects-per-thousand measure. The initial quality goal for the Six Sigma methodology was no more than three defects per million parts.

Then, in the 1990s, Jack Welch, CEO of GE, popularized Six Sigma by dictating its use across the whole of GE. The resulting profit and quality gains that GE touted led to Six Sigma’s being implemented in many large corporations. The claimed Six Sigma–generated ...