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Six Sigma-fying Your IT Department?
Saqib Ali asks: "These days all the major corporations are looking at Six Sigma methodology to improve their processes. I am planning to take a Six Sigma Green/Brown belt class in March. I work for the IT department, I have a statistics background, and I've studied statistics in university as well. I can understand Six Sigma being used in Production/Manufacturing facilities, but it is hard for me to figure how to apply Six Sigma in IT. Are any other readers using Six Sigma methodology for IT? If so what are some of the things that it can be applied to? As part of the training class, I have to come up with an idea for a Six Sigma analysis project. Though the project doesn't have to be IT related, but I would like it to be, so that I can see its application in real life. Any ideas for the project?"
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The new Scott Adams Dilbert book ( The Way of the Weasel - and no, I'm not going to look it up on Amazon for you! ) has a small section on six sigma madness, if you need perspective.
It's called process capability analysis in the textbooks.
Six sigma arose out of a rigorous statistical method of analysis of manufacturing data. Basically you plot some measurement of some characteristic of a device being manufactured over a large number of samples. This provides a characterization of the manufacturing process. Hopefully the data you chose to gather is normally (in the formal sense) distributed and you can assign a mean and standard deviation (sigma) to the data. You also examine where the actual specification for the measured characteristic lies. A simple way to characterize the location of the specification is in terms of the number of standard deviations (sigmas) that the specification is away from the mean measurement. Six sigma is simply a statement that the specification is six standard deviations away from the mean. Measurements outside the six sigma range denote defects.
All of this is very cut and dry stuff that has been used in manufacturing for decades. Six sigma was 'popularized' when Motorola adopted it as a quality goal for their products company-wide.
How does this apply to software development? I don't have a clue. How the hell do you establish a process capability measurement for a software development process in a rigorous fashion? Good Luck.
IMHO this is just the latest quality fad that is rippling through the management/consultant community. What next? Re-engineering rises from the ashes again?
"Six Sigma" is a buzzword name given to the methods of W. Edwards Deming, who advocated a methodology that depends on having objective, numerical measures of results. In a nutshell, the methodology tells us to understand the causes of variability in product and process design, and to work systematically to identify, understand, and eliminate causes of variation that propogate into the metric for goodness that we choose. Beware trying to apply these techniques when the metric for goodness isn't even clear.
These techniques are used heavily in machining and electronics because they provide an objective, rationally based methodology for improvement. If you are building car cylindars, you use these techniques because if your competitor has more perfectly round cylindars than you do, cars built with them get better mileage and are more reliable and durable.
The Six Sigma methods are difficult to apply in settings where an objective numerical measure of "goodness" isn't available. This is often the case in software design, when features and "ease of use" are the objective. One area where it can be applied quite well in software is in performance monitoring and tuning. Run duration is quantifiable, repeatable, and "faster is better" translates run times into a raw quality measure.
Trying to use statistical methods on metrics that aren't objective or aren't easily quantified. Beware of using bug or defect coutns unless the failure mode is extremely well defined. Crap like "lines of code" or "number of methods" may be objective but there is no way to translate them into an overall measure of quality.
Statistical techniques are a very powerful tool, but they are just that -- a tool. Just like a hammer isn't useful if you need to sand wood, don't expect "Six Sigma" to be the solution to every quality problem.
From the site:
Six Sigma is a rigorous and disciplined methodology that uses data and statistical analysis to measure and improve a company's operational performance by identifying and eliminating "defects" in manufacturing and service-related processes. Commonly defined as 3.4 defects per million opportunities, Six Sigma can be defined and understood at three distinct levels: metric, methodology and philosophy...
With such a description, I wouldn't touch it with a ten foor pole.
the pun is mightier than the sword
1. You have a problem
2. Collect stats about it
3. Analyse those stats to identify the problem
4. Some sort of magic goes here to get from problem to solution
5. Apply solution
6. Collect stats again
7. Calculate saving and claim is a 6Sigma saving
8. Claim that the solution can be applied elsewhere for some vague future saving
The problem is that the saving comes from applying the solution (Step4) not from the process of Six Sigma.
Step 4 is done by the skilled engineers who know what solution fixes what problem, not the Six Sigma MBA who has no special expertise in the process.
If the fix can't be applied because the guy is collecting statistics in Step 2) then he is causing the company damage by delaying the fix.
His own salary is also a cost and the load he puts on the skilled engineers while trying to 'learn' their skill also costs money.
In order to obtain statistics, you have to know what the possible causes are, so in the real world, they go to the engineer who already knows the problem and contrive a set of stats to collect that prove that solution.
Then there's step 8, claim it will be re-used.
If you look at the examples Six Sigma people give, its stuff like a leaking airconditioner pipe.
If you have a leaking air-condition pipe, you hire a plumber or buy a book on plumbing, you don't look through Six Sigma projects looking for one that might turn up useful information.
Quite simply the chances of someone re-using this information is negliable and its the fix in step 4 is the thing that would be reused and that isn't a Six Sigma step.
So no, it just fluff to keep middle managers employed. That is why every company that uses it continue to increase costs. GE increased profit came from increase *sales* and economies of scale, not Six Sigma.