Six Sigma
Six Sigma is one of the most popular quality management methodology used in the industry today. It started in 1986 as a statistically-based method to reduce variation in electronic manufacturing processes at Motorola. Originally, it is based on the “Total Quality Management” concept and adapted to the electronic industry but overtime, it is being “advertised” as a lot of different things with different meanings depends on who is explaining it.
When I worked at Motorola in the late 1980s, Six Sigma is only used within the company on the improvement of wafer, a thin slice of semiconductor material, upon which microcircuits are constructed. This manufacturing process is error-prone and expensive so by applying measurements (Six Sigma is 3.4 defects per one million opportunities) we can reduce the number of defects accordingly. However, other people had adapted the technique and terms into other areas such as business, finance, software and overtime, Six Sigma has evolved into many things to many people.
Today, according to Motorola training, Six Sigma is a metric, a methodology, and a management system.
From the metric view, Six Sigma is used as a scale for levels of ‘goodness’ or quality. A Six Sigma equates to 3.4 defects per one million opportunities (DPMO). The term ‘Six sigma’ come from mathematic and statistic term as a unit of measurement in variation.
From the methodology view, Six Sigma can be used as a business improvement that focuses an organization processes by: 1) Understanding and managing customer requirements, 2) Aligning key business processes to achieve those requirements, 3) Utilizing rigorous data analysis to minimize variation in those processes, 4) Driving rapid and sustainable improvement to business processes. To implement these processes, organization must apply the improvement model called DMAIC which is the acronym for: Define opportunity; Measure performance; Analyze opportunity; Improve performance; and Control performance..
From the management view: Six Sigma advocates that metrics and methodology is not enough to make improvements over time. It is more important to treat Six Sigma also as a management system for executing business strategy by 1) Align business strategy to critical improvement efforts; 2) Mobilize teams to attack high impact projects; 3) Accelerate improved business results; 4) Govern efforts to ensure improvements are sustained.
Basically, Motorola emphasizes that you must use all three views to achieve improvements that are sustainable over time. Six Sigma’s process metrics and methodology must be applied to improvement opportunities that are directly linked to organizational strategy. To implement Six Sigma methodology, organization must create teams with team leaders. These people need to be trained in Six Sigma’s methods (This is where many consultants come in and that is why Six Sigma become very popular). The team must know how to use metrics and improvement tools (More training and more tools), as well as knowing how to communicate with internal, external customers and suppliers as they are part of the critical processes of the organization’s delivery chains. After several trainings, team members may achieve certain ranks such as Black Belts, Green Belts etc. adapted from the Karate system which denote people with different qualifications, and expertise. Six Sigma team leaders (Black Belts) know how to use measurement tools at each phase of the improvement to define, measure, analyze and control variation in process quality, and to manage people, teams and communications.
I have experienced the use of Six Sigma in electronic manufacturing process when I worked at Motorola. However, today there are so many different explanations on the application of Six Sigma into other areas and it is difficult to make a objective observation to determine how it works. For example, to achieve Six Sigma in software, does it means software product must achieve no more than 3.4 defects per million line of code? I have seen many software companies claimed on achieve “Six Sigma” but I do not know what it means so I admit my ignorance in this area and let the expert explain it.
Sources
- Blogs of Prof. John Vu, Carnegie Mellon University
