Six Sigma Had a Demise?

Rick Bohan

I happened across an article, just a couple of weeks ago, about the alleged demise of Six Sigma.   (Read the article here.) Now, I’ve never been either a huge fan or a detractor of Six Sigma.  I myself am not a Six Sigma any-kind-of-belt but I took a fair amount of statistics in college and grad school, some of it pretty advanced.  All to say, I’m aware of both the utility and the limits of statistical tools of the sort Six Sigma practitioners use.  I’m also aware that Six Sigma isn’t just a bundle of statistical tools, rather it’s an overall approach to analyzing and addressing variation of both processes themselves and the outputs they deliver.  Finally, I’m aware that, the only thing the media like better than boosting a particular management “fad”  (and I use that term cautiously, mainly because I don’t like it.  It’s most often used by lazy journalists writing the sorts of articles I’m about to refer to)…is tearing management “fads” apart.  The article in question isn’t quite the latter but it is a good example of an article that gets a lot of stuff wrong as it makes the case that Six Sigma is, perhaps, passe`.  Mind you, it’s not a bad article…in fact, it’s well worth reading.  But…well, let’s take a look at the article in a bit of detail and I’ll go over some of my quibbles.

First, there’s this:

“The name [Six Sigma] refers to a statistical model, based on deviations on a bell curve, that dictates the number of acceptable defects per million manufacturing steps.”

I’ve never heard Six Sigma defined as the number of acceptable defects per million manufacturing steps.  It’s more often defined as the number of defects (I’m not altogether sure what an “acceptable defect” is) per million units of output, regardless of the number of manufacturing steps.  It’s a small thing, to be sure, but when the basic definitions are wrong, one does wonder about the validity of the rest of the argument.

Then, this:

“…as GE’s fortunes diminished, so has interest in Six Sigma.”

Now, this, strictly speaking, is probably true.  Of course, two things can happen at the same time and not be at all related.  It may not be the author’s intention but a reader might be forgiven for understanding him to say that GE’s diminished fortunes are related to, perhaps even caused by, Six Sigma.

Finally, we get to the part (or parts) of the article that we always know is coming…the part where the approach itself, rather than flighty, unfocused managers, is blamed for its demise:

“And as with all fashions, once Six Sigma was picked up by the masses, fashionable companies lost interest and moved on to the next big thing. “These things have a life cycle: They get popular and then people start looking for something else,” says Art Swersey, a professor emeritus of operations research at the Yale School of Management. “These things run their course, and it has run its course.”

“Fashionable” companies lose interest? “Fashionable” companies move on to the next big thing?  People start looking for something else?  The writer might have dug into the issue of just why perfectly effective approaches are cavalierly adopted, then dropped by managers charged with creating value for shareholders and society.  But we’re just left with the notion that Six Sigma just wasn’t…”fashionable” enough.

After that,  article nearly spins out of control:

“Six Sigma’s decline was also a symptom of a broader change in the corporate world, where innovation became more valued than efficiency, and technical precision was no longer a differentiator. Silicon Valley’s culture of “move fast and break things” meant business leaders were less concerned with reliability and more focused on game-changing discoveries.”

So…finding and eliminating process variation that detracts from customer value and increases operating costs is no longer of interest to today’s managers?  Wow…who knew?

It’s true that Six Sigma, like lean and TQM and MBO and SPC and on and on, has gone through a cycle of being over-hyped, then discarded when it proved to actually require some investment on the part of the organizations that made half-hearted attempts to implement it.  I’ve experienced this cycle in microcosm when clients hire me to help them implement lean enterprise methods throughout their organization…then quit before they so much as organized the plant floor.  I know of organizations that paid to have any number of their employees trained in Six Sigma methods, only to ignore those employees entreaties for kicking off improvement projects once they got back home.

Don’t get me wrong…I think Six Sigma is misunderstood and misused.  (And I confess that whole “green belt/black belt” thing rubs me the wrong way.)  But this isn’t the fault of the approach or the tools that it comprises.  It’s the fault of short-sighted, impatient managers not interested in devoting themselves to the hard work required to make any organization change effort a success.


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