Six Sigma is a quality measure that aims for near-perfection. Six Sigma refers to a method and discipline that is data-driven and focuses on eliminating defects.
Six Sigma has its roots in Carl Friedrich Gauss’ (1777-1855), the inventor of the normal-curve concept. Six Sigma, as a standard measurement for product variation, dates back to Walter Shewhart’s 1920s work. Shewhart proved that a process must be corrected when it is three sigma off the mean. Many measurement standards (Cpk, Zero Defects, etc.) Bill Smith, an engineer at Motorola, was the first to coin the term Six Sigma. Bill Smith and Mikel Harrer had written a research report that codified the new Quality Management System. The report emphasized the connection between the product’s performance on the market and any adjustments necessary at the production point. The report indicated that performance is improved by reducing the number non-conformities. The report was revolutionary, because it led to the introduction of ‘logical filters’ that are used as a tool for solving problems. Bob Galvin then became the Motorola CEO and was a pioneer of this four-stage system. It was with his support that this logical framework evolved into Six Sigma. The four stages are called Measure, analyze, improve and control.
MethodologiesThe Six Sigma approach is a strategy that uses measurement to focus on the improvement of processes and reduction of variations.
Two sub-methodologies of Six Sigma are used to achieve this.
DMAIC: DMAIC is a project management methodology that has five phases. Define the project, the system, customer voice and requirements. Data collection and measurement of key processes aspects are necessary to calculate the Process Capability. Analyze data to verify and investigate cause-and effect relationships. Determine the relationship and ensure all factors are considered. Search for the root of the problem. The data analysis can be used to improve or optimize the process using techniques like design of experiments, mistake proofing or poka yoke. Pilot runs are used to determine the process’s capability. Control the process in the future to make sure that deviations from target are corrected prior to defects. Implement control measures such as visual workspaces, production boards or statistical process control. This process must be repeated until desired quality levels are achieved.
DMADV : The DMADV Project Methodology, also known by the acronym DFSS (“Design For Six Sigma”) has five phases. Measure CTQs, identify product capabilities, production processes capability, and assess risks.
Design a better alternative that best suits the analysis done in the prior step. Verify the designs, run pilot tests, implement the production processes and give it to the owners.
Customer-driven. It is more concerned about the process than the outcome. It is more proactive than reactive because it looks for ways to make improvements before problems are identified. Small businesses that are able to achieve the Six Sigma certificate will be a cut above their competition. The Six Sigma certification is very valuable for specialty manufacturers who produce precision goods.
Six Sigma may lead to bureaucracy and rigidity in production processes, which can stifle innovation and create delays. The focus on customer satisfaction may go too far, causing companies to ignore internal quality-control procedures that are beneficial for them. In some cases, a cheap measure that may result in a slightly higher defect level is rejected to favor a costlier measure that will achieve Six Sigma. But this could have a negative impact on profitability. The implementation of six sigma for small companies is very expensive. Six Sigma certification can only be obtained by enterprises that have employees who have received training at Six Sigma certified institutes. It is important to have a lot of training even if you don’t want to be certified to use Six Sigma. Even if a small business only has one employee, it is unlikely that they can afford to pay for such intensive training. Small businesses needing to be flexible and creative find Six Sigma’s system of analysis stifling. It is bureaucratic and time-consuming.
