Six Sigma & Projects
Background | Who's Who | Process DMAIC | Process DFSS | Things to Know
Background
What is Six Sigma? It is a statistically based process improvement methodology that arose from the manufacturing sector and is based upon principles such as Hoshin, lean and TQM.
Six sigma was invented by male engineers from Motorola back in the 1970s-1980s, which probably accounts for the somewhat militant titles of practitioners - champions, green belts, black belts and master black belts. It is focused on reducing variability within processes and the term six sigma relates to the number of defects per million opportunities. The folks over at iSixSimga provide more information than most could need on this topic.
As person who has used six sigma, I know the power inherent in this methodology when it is done well. When used judiciously and supported with appropriate levels of investment, it is a tool that can free up substantial bottom line savings for an organisation.
This particular methodology is no better or worse than any other management fad. The trick is to stick to the fad long enough for it to become useful. Organisations that have truly benefited from six sigma have done so because they embraced the methodology and made it part of the corporate culture.
The methodology is very much based upon statistical analysis of problems and design of solutions. It has much akin to evidence based medicine and finds substantial resistance in most businesses. Since business has run on instinct rather than facts quite successfully for many years it is often a challenge to introduce a statistically based process improvement methodology. In fact, without significant senior management support six sigma initiatives are doomed to become merely passing fads.
One thing that novices tend to notice with six sigma is the preponderance of jargon. Practitioners ramble on about CTQs, RCA, PSTS, HOQ, etc. As with most jargon, it all means something, but most of all it can become a sort of cultural glue in the organisation. I've talked with six sigma practitioners from the US, Europe & South America & the jargon is an important way for us all to overcome communication problems. And, the jargon in six sigma is no worse than that in other areas of the quality industry.
Who's Who in the Six Sigma Zoo?
There are several traditional pre-defined roles in six sigma:
- champions - these are the business managers who support & encourage six sigma activities within the business
- black belts - these are the people who have full time jobs in running six sigma projects
- green belts - these are people who are trained but only work part time on six sigma projects
- master black belts - these are the people who live & breathe six sigma, overseeing & monitoring all project activity
There are also some other roles - orange & yellow belts, etc. These are additions to the traditional roles and are not always agreed upon by six sigma practitioners.
Key Process Steps - DMAIC
The DMAIC process is used for process improvement activities, those where the existing process is not "out of control", or "broken".
- Define - define the goal, problem, customers, inputs & outputs (including defect levels)
- Measure - the existing process to identify bottlenecks & inefficiencies, use a measurement plan to ensure repeatable measurements are taken
- Analyse - the data to determine the root causes, process map the 'as is' processes, determine sources of variation and prioritize the opportunities for improvement
- Improve - determine the improvement plan and implement it
- Control - monitor the improvements to ensure that they do not revert to the old ways, tweak the new process to ensure it is optimal
Key Process Steps - DFSS (a.k.a Design for Six Sigma or DMADV)
The DFSS process is used where the existing process is either too broken to fix or where a new activity is being undertaken. It is often used in new product development or software development projects. Many practitioner organisations have adapted DFSS/DMADV for these purposes.
There are many variants to DFSS/DMADV around now, for example some people will mention: DFSS, DMADOV,DCCDI, IDOV, or DMEDI - try iSixSigma for more information on these variants.
In DMADV the first 3 steps are the same as in DMAIC, then it diverges:
- Define - see DMAIC
- Measure - see DMAIC
- Analyse - see DMAIC
- Design - the solution to meet customer needs
- Verify - that the solution implemented has met customer needs
Important Things to Know About Six Sigma
- Thomas Pyzdek's 101 Things A Six Sigma Black Belt Should Know
- Without strong management support it is likely to be less successful
- You must learn to love statistics & quantitative analysis
- Not all projects fit properly into the six sigma world, but the discipline can still be useful
- You can even follow the six sigma methodology for very small projects - I once used it for a 3 day project
- As with all methodologies - use it pragmatically, leave out the bits that don't make sense for a particular project (but it is important to know why you are leaving out those bits)
- There is a vast amount of jargon
