In layman’s language, Six Sigma means great and fast improvement, which leads to virtual perfection. Another indicator of a successful application of the Six Sigma methodology is the degree of breakthrough. Sometimes, when customers demand zero defects at any cost, suppliers are forced to add an inspection stage to their system regardless of its process capability. Achieving zero defects for the Six Sigma’s sake leads to more waste and breeds undesirable approach toward Six Sigma. In theory, companies can achieve Six Sigma, but reality is sometimes different. It may be difficult to achieve Six Sigma level performance through process improvement using statistical techniques alone. Companies must consider using poka-yoke or failure-free methods to eliminate remaining opportunities for mistakes. Remembering Bill Smith’s Six Steps to Six Sigma, it’s possible to see the potential of poka-yoke. Smith’s six steps to Six Sigma are listed below:

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