Six Sigma without the belts and the mysticism

Six Sigma has a branding problem in the opposite direction to TQM. Where TQM sounds dated, Six Sigma sounds like a cult, with its black belts and green belts and talk of sigma levels, and plenty of sensible people wrote it off as consultant theatre. That is a shame, because underneath the ceremony is one of the most effective quality methods ever devised. Motorola, which coined the term in the 1980s, credited Six Sigma with saving it something in the order of 16 billion dollars over about fifteen years, and General Electric saved billions more when Jack Welch made it central to how the company ran.1

Strip out the mysticism and Six Sigma is two plain ideas. First, variation is the enemy: a process that is sometimes brilliant and sometimes terrible is worse than one that is reliably good, because the customer feels the bad days and you cannot plan around chaos. Second, use data to find where the defects actually come from, rather than fixing whatever the loudest person blames. That is it. The belts are just a way of certifying who has learned the method. You do not need one to use the idea.

00.20.50.811Define1Measure1Analyse1Improve1Control
DMAIC: the five steps under all the belts and jargon. Indicative. Source: Six Sigma / DMAIC

DMAIC: the method under the jargon

The engine of Six Sigma is a five-step cycle called DMAIC, and it is genuinely useful even if you never say the word "sigma". Define the problem precisely, in terms the customer would recognise. Measure what is actually happening, with real data, not impressions. Analyse the data to find the real cause, which is very often not the one everybody assumed. Improve the process to remove that cause. Control it so the improvement holds and the problem does not creep back. It is disciplined common sense, and its power is in the order: most people jump from a vague problem straight to a favourite solution, skipping measure and analyse, which is exactly why their fixes do not stick.

The solution, as a DMAIC walkthrough

Fix a recurring problem the Six Sigma way

  • Define: state the problem as the customer sees it. "One in twelve orders ships late", not "logistics is a mess".
  • Measure: get real numbers. How late, how often, on which orders, from when. Impressions are not data.
  • Analyse: let the data point to the cause. It is usually not the one everyone blames. Follow the evidence.
  • Improve: change the process to remove that specific cause, and test that it actually worked.
  • Control: lock it in. Monitor the number so the problem cannot quietly return once attention moves on.

The discipline people skip, and pay for

The single most valuable thing Six Sigma enforces is the gap between spotting a problem and choosing a fix. Human beings hate that gap. We see a problem and immediately reach for the solution we already liked, which is how organisations spend years fixing the wrong cause with confidence. DMAIC forces you to measure and analyse before you improve, so your fix aims at the real cause rather than the obvious one. That discipline is unglamorous and it is where the 16 billion dollars came from, because a fix aimed at the right cause works, and a fix aimed at the wrong one just moves the problem.

Questions to run a problem through DMAIC

  • Have we defined the problem as the customer would, not as we prefer to?
  • Do we have real data, or are we acting on impressions and blame?
  • Has the data told us the cause, or did we decide the cause first?
  • Are we fixing the real cause, or the one that was easiest to assume?
  • Once fixed, what number will tell us if it creeps back?

Ignore the belts and the Greek letters. Six Sigma is two ideas, reduce variation and follow the data, delivered through one disciplined cycle that forces you to measure and analyse before you leap to a fix. That discipline is why it saved Motorola and General Electric billions, and it works just as well on a small business problem as on a factory line. You do not need a black belt. You need the patience to find the real cause before you spend money on the wrong one, which is the one thing almost everyone skips.

Notes and sources

  1. Motorola credited Six Sigma with around 16 billion dollars in savings, and General Electric saved billions under Jack Welch. iSixSigma, Six Sigma costs and savings. Link. ↩
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Stefan Gauci Scicluna

Compliance and quality assurance adviser, lecturer and author of six practical business books. He writes on compliance, quality, procurement and training, grounded in real, documented company cases. Views are his own.

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