Let's fix Six Sigma!

[Bev D]

I'm brave enough to say I don't and I never did and most people who are actual practitioners - who are not hacks just out to sell you something, get their ticket punched, or are just casual browsers of 'quality stuff'* - don't believe in it and never did. It's a false issue.

*and these people live off of every fad including Deming and TQM and Lean and BPM and...I remember the consultants, people magazine class articles and even college professors who jumped on the SPC bandwagon after "If Japan can, why can't we" documentary because they smelled money. They were silly perpetuators of all kinds of myths and stupidity about SPC - but that didn't make SPC wrong. those people are leaches who have now moved on to 'six sigma' and are probably even now looking for the next blood source. Greed will always be with us. It does us no good to continually rail against it; we must focus our energies on the good we can do. We need to lead by example.

There are plenty of coincidental artifacts that are real and could use or efforts to extinguish: among them are the Cpk/Ppk fallacy, the dreaded fishbone diagram, the AIAG Gage R&R, the over use of the Normal distribution for individual values, etc. that are much more widely used and result in actual decisions that affect quality. Why don't we turn our efforts to doing some real good instead of "fighting the civil war" all over again?

 

[BradM]

I'm curious ... does anybody still believe in the nonsense of the 1.5sigma "drift" / "shift" / "correction" / "dynamic offset", or the 3.4 dpmo, or in calculating dpmo ? Anyone brave enough to put their hand up ?

Hand goes up...

Ok... much ink has been spilled at this site regarding Six Sigma. To your above, I believe that it is a plausible notion, and one which probably worked for Motorola:

Six Sigma was a way for Motorola to express its quality goal of 3.4 DPMO where a defect opportunity is a process failure that is critical to the customer. Motorola set this goal so that process variability is ±6 S.D. from the mean (Breyfogle et al.,2001, p. 39). They further assumed that the process was subject to disturbances that could cause the process mean to shift by as much as 1.5 S.D. off the target (Montgomery, 2001, p. 23). Factoring a shift of 1.5 S.D. in the process mean then results in a 3.4 DPMO (see Montgomery p. 24 and Breyfogle et al., 2001, p. 40). This goal was far beyond normal quality levels and required very aggressive improvement efforts. For example, 3 sigma results in a 66,810 DPMO or 93.3% process yield, while Six Sigma is only 3.4 DPMO and 99.99966% process yield (these computations assume
a 1.5 S.D. shift in the process mean).

Journal of Operations Management 21 (2003) 193–203
Six Sigma: a goal-theoretic perspective
Kevin Linderman∗, Roger G. Schroeder1, Srilata Zaheer2, Adrian S. Choo3

That to me, is a plausible notion. But... therein lies the effort to take a good idea, or test the model, in another arena. Then, the problems occur. What worked for Motorola does not mean it will work for everyone else; akin to taking one organization's QMS, replace company name, and make it your own.

But likened to the "why do bad things happen to good people" notion, it amazes me how much good hard-working consultants have to go through to truly make advances with systems, but all a snake oil salesman has to do is hisss the Sixxx Sigma, and people just sign purchase orders.

There are good tools and good people under that umbrella, but the catch phrase needs to be removed. Let's apply the 1.5 shift and call it 9 Sigma!!

 

[somerqc]

Thank you Bev.

This reminds me of personal experiences in sports - in one sport you would constantly hear negative comments if someone did well and in another sport is was almost always good comments when someone excelled.

Unfortunately, unless we take Bev's words to heart, the Quality professional will continue to be like the first sport I was involved in and never move onto the second sport. In addition, as long as we are like this the consultants that are just out to make a buck will continue to ruin our reputation.



Looking to NOT be a cost, but a contributor to increasing profit,

John

 

[BradM]

Thank you Bev.

This reminds me of personal experiences in sports - in one sport you would constantly hear negative comments if someone did well and in another sport is was almost always good comments when someone excelled.

Unfortunately, unless we take Bev's words to heart, the Quality professional will continue to be like the first sport I was involved in and never move onto the second sport. In addition, as long as we are like this the consultants that are just out to make a buck will continue to ruin our reputation.



Looking to NOT be a cost, but a contributor to increasing profit,

John

Agreed. Methinks I better elaborate a bit on my previous post.

The concept of the shift, six sigma, and such is entirely plausible, in theory, and as it applies to normal distribution discussions. Then again, perfect parenting and perfect marriages are also plausible, in theory.
The consulting practice of Six Sigma and how it is used as a panacea for every situation is deplorable.

Funny.. it's getting to every time I hear the phrase Six Sigma, the thread of Sham Wow comes to mind.

 

[Stijloor]

<snip>Why don't we turn our efforts to doing some real good instead of "fighting the civil war" all over again?

Bev,

What would you suggest? Please provide me with some suggestions about what companies should do....

Stijloor.

 

[bobdoering]

"A defect occurs when a product doesn’t meet its specification. The most obvious way to reduce defects is to change the specification. A broader specification means fewer defects. This may sound silly but it’s exactly what was advocated by the founder of Six Sigma, Bill Smith. Deming’s approach to quality was to reduce variation."

Is Bill Smith wrong? Is Demming right?

Check it out - "It depends!"

Reducing variation on the surface sounds great - but the down side is it can lead to overcontrol. Overtightened specification really can have a negative economic impact. Why pay more for tighter tolerances if the product performance is not improved? Who are you trying to impress with your target shooting skills? Painting the broad side of a barn with a paintball gun? Sure it's fun....but still....

Do not define "quality" by specification or reduction of variation. Define quality by economic control - adjust your process only when you need to.

When debating the issue, be careful of picking sides. You may find occasions when one side is right and other situations when the other side is right. This just happens to be one example...

Hey...."It depends!" (Now that should be a Six Sigma concept, eh? )

 

[Paul Simpson]

Just another thought

Now don't all jump down my throat but is anyone interested in ISO developing a standard (or more than one!) on six sigma?

Your thoughts?

 

[bobdoering]

Re: Just another thought

Now don't all jump down my throat but is anyone interested in ISO developing a standard (or more than one!) on six sigma?

Your thoughts?

Oh, please no.

 

[Bev D]

Re: Just another thought

Now don't all jump down my throat but is anyone interested in ISO developing a standard (or more than one!) on six sigma?

Your thoughts?

oh god no.

how do you standardize: it depends?

 

[Bev D]

Bev,

What would you suggest? Please provide me with some suggestions about what companies should do....

Stijloor.

I will have to ponder on this a bit as I'm rushed for time right now...

but a good start is to become statistically literate in an applied sense.
Self assessment and always looking for a better way is critical: what is working and what isn't
delete powerpoint from your office software
keep studying and NEVER invest personally in a single "guru". living or dead...

understand that there is no one right 'way', but there are many, many incorrect ways and answers for any given problem. Question everything.

Companies should invest in "in house experts" whose job is to learn mentor and coach. They should be constantly learning and trying new ways from all industries. but the in house experts have to be applied not theoretical. they have to have "grease under their fingernails".