It is a methodology for business’ processes improvement. Its aim is to minimize the quantity and intensity of possible mistakes made in a given organization and, from that improvement, to bring more quality to the processes for them to work more effectively in the achievement of their goals. It is not a methodology as extended as others because it is specially demanding:
Six Sigma is intense and rigorous, and it entails a thorough inspection of the way everything is done. Six Sigma sets ambitious business objectives and measures performance in a way that forces accountability. It doesn´t allow a management team to become complacent, but, rather, it exposes waste that otherwise would remain largely invisible. Six Sigma takes a business out of its comfort zone (Gygi et al, 2005).
The name of the method comes from a statistical variable, called sigma, that stablishes how a given process behaves in contrast to what is expected from it. A poor quality process, not bringing the results expected from it, works at a 1 or 2 sigma level; a high quality process works from 3 sigma on, This methodology establishes that an excellent quality cannot go lower than 6 sigma, and proposes a way of achieving this standard based on the capacity for recognizing the exact causes of the performance that company shows, for then improving them with clear detail.