Started by Motorola Inc. in an effort to reduce defects in manufacturing, Six Sigma can also be applied to other business processes for the same purpose. As the methodology evolved, emphasis has been less on finding defects per million opportunities (DPMO) and more on improving the business methodology that focuses on:
- Understanding and managing customer requirements.
- Aligning key business processes to achieve those requirements.
- Using rigorous data analysis to minimize variation in processes.
- Promoting fast and sustainable business process improvement.
At the core of the methodology, there are two models; the DMAIC model – used for existing processes that fall below specification and seek incremental improvement – and the DMADV process – an improvement system used to develop new process or products at the Six Sigma quality levels.