Quality Assurance: Software Quality Assurance Made Easy pdfdrive com

Chapter 3: The Six Sigma Model
The Six Sigma Model consists of tools and techniques for improvement of
processes. Bill Smith introduced this concept in 1986 while he was still with
Motorola. Jack Welch used this as a business strategy in 1995 at General
Electric. At present, various industrial sectors use the Six Sigma Model.
The Six Sigma Model improves the output quality of a process through
identification and removal of the causes of defects. It also minimizes variability
in the business and manufacturing processes. This model uses quality
management methodologies and creates a special group of experts within the
organization.
Every project adheres to a specific sequence of steps with defined value targets
like reduce pollution, reduce cycle time of a process, reduce costs, increase
profits, and increase customer satisfaction. The term Six Sigma came from a
manufacturing statistical modeling of processes. A process can have a sigma
rating to indicate its percentage of defect-free products.

---

The Doctrine of the Six-Sigma Model
The Six Sigma model asserts that process results will be stable and predictable
through continuous efforts. It is possible to measure, control, analyze, and
improve business and manufacturing processes. Furthermore, quality
improvement is sustainable if the entire organization commits to it.
The Six Sigma model focuses on attaining quantifiable and measurable financial
returns. Its emphasis is on passionate and strong management support and
leadership. It is committed to decisions based on verifiable statistical methods
and data, instead of guesswork and baseless assumptions.

---

The Six Sigma Methodologies
The Six Sigma Model has two methodologies, namely DMAIC and DMADV.
DMAIC is for improving present business processes while DMADV is for
creating new process designs or new product.