A data-driven management philosophy developed by Motorola for eliminating defects, waste and quality-control problems in manufacturing. The basic idea behind Six Sigma is that if one can measure the amount of "defects" in a process, one can systematically determine how to eliminate them, getting as close to zero defects (i.e., perfection) as possible. In order to achieve Six Sigma, the process cannot produce more than 3.4 defects per million opportunities (opportunity being defined as a chance for nonconformance or not meeting the required expectations).
Six Sigma is broken down into two different processes:
- Six Sigma DMADV -- a process that defines, measures, analyzes, designs and verifies new processes or products that are trying to achieve Six Sigma quality.
- Six Sigma DMAIC -- a process that defines, measures, analyzes, improves and controls existing processes that fall below the Six Sigma specification.
The term is derived from the Greek letter sigma, a mathematical term that represents a measure of variation.
According to Motorola, Six Sigma has had non-manufacturing applications in transactional processes, such as billing and customer support.