Advantages & Disadvantages of Six Sigma

Six Sigma is a popular process improvement methodology that started in the manufacturing sector and has spread to other areas as well. Some companies have seen tremendous success, while others have abandoned the methodology or found it too overwhelming to support.

Based on Data

In Six Sigma, decisions are made based on empirical evidence, not just on assumptions and anecdotal evidence. This includes determining the need for a project, determining the cause of the problem being addressed, and deciding what improvements will be made. In all these cases, data is required for decision making.

Proven Success

Beginning with Motorola, many large companies have successfully rolled out Six Sigma initiatives and driven positive change in their organizations. The results have benefited customers, employees, and shareholders.

Sustainable Solutions

The DMAIC and DMADV processes are specifically designed for sustainable solutions. In DMAIC, the improvements to a process are confirmed with data, and an entire phase is devoted to ensuring that the gains are sustained. In DMADV, which is used for creating new products and processes, a similar mindset holds.


As the saying goes, "Do you want it fast or do you want it right?" In order to effectively use the Six Sigma methodology, a substantial amount of time must be allowed for a project. It does not provide simple fixes, and at times the people involved can become frustrated with the time required to systematically follow the improvement model.

Training Requirements

In traditional Six Sigma implementations, employees go through extensive training to become Six Sigma project leaders (Black Belts and Green Belts) and sponsors (Champions and Process Owners). For the Black Belt role in particular, training can take several weeks or more, and occur over a period of months. This is not feasible in some environments.

Corporate Focus

Although the principles underlying Six Sigma could certainly be made applicable to small business and organizations, it is primarily an option for larger corporate organizations. Overwhelmingly, the majority of training and information available is geared toward that sector. This makes it difficult for other groups to see any benefit in adopting the methodology.