What is Six Sigma?

Six sigma is a statistical concept, coined by Phillip Crosby. It is used to describe the state of zero defects or a state, which is as close as possible to near perfection. Six Sigma quality means going from approximately 35,000 defects per million operations (which is the average for most companies, including GE) to less than 4 defects per million in every component, in every process that the company undertakes every day.

Many companies such as Motorola, Texas Instruments, Eastman Kodak and Allied Signal began Six Sigma before GE did. GE documented their discoveries and successes and adopted many concepts and disciplines of Motorola’s Six Sigma methodology.

Six Sigma demands an effective use of data to analyse business issues. The focus of Six Sigma is on thorough understanding of key processes and on the analysis of how the key process input affects the process output. After the key inputs that assure sustainability of any process are identified, quality enhancement is simplified by linking the quality control plan to controlling input rather than output.