Lean-Six Sigma: What do critics say?

[Govind]

Lean Manufacturing is also a combination of 1960s to 1980s Industrial Engineering tools, packaged to meet the modern industrial necessity of JIT, No WIP, Cycle time reduction,Value stream resulting in bottom line improvement.

Lean also has X belt certification, Consultant implementation, Massive training cost, big corporations endorsement. I see no difference from “Six sigma” point by point. Both methodologies complement each other. Don’t get me wrong; I believe in the synergy of both Lean and Six sigma.

Iam not sure why Six sigma was singled out by various professionals and was put on trial. How did Lean Manufacturing escape from the critics?

Regards,
Govind.

[Wes Bucey]

My guess is that Lean created the image it was all about efficiency and had none of the bad image of "Quality Qops" (QQ) policing (and narcing on miscreants [contrary to Deming]) production to "detect" nonconformance. Six Sigma took on some of the trappings of QQ and stepped on a few toes so they got lambasted by QQ who didn't like the invasion of their (our?) turf. Sadly, both the QQ and 6S folk spend too much time patting themselves on the back about how good they are while the Lean folks just go ahead and do their thing and let the results speak for themselves with no phony balony "projections of savings." They actually trot out the books and show the savings.

The sharp guys over in ASQ dropped the Lean buzzword and called themselves "Advanced Manufacturing" when they (we - I belong to that Division, among others) created a new Division.

It is all in marketing and perception. Marketing can be a fun activity all by itself.

There are "some" things to criticize in the Lean tool bag, especially the part where we gloss over the fact somebody in the supply chain ultimately has to hold inventory because the production lead time would foul up the rest of a Lean chain.

[Steve Prevette]

Here are the reasons I think Lean has not been attacked as Six Sigma was:

1. It is a set of tools. Tools for optimizing inventory levels have been around for a long time.

2. It is described in open literature. You don't have to pay megabucks to learn "lean". (Learning about lean is lean)

3. It uses existing Operations Research and Industrial Engineering principles, and doesn't sell itself as a replacement for OR and IE.

4. It has not tried to create a bunch of "belts" a new class of people to replace managers and engineers.

5. It has not been sold as "instant pudding" - most literature is good at documenting the pluses and minuses of lean.

6. It doesn't have a Mikel Harry.

[Govind]

Having read 3 real busy Six sigma threads in this forum and elsewhere..I understand the frustration of critics on Six sigma is

not as a Quality Methodology,
not the Tool box,
not the Body of Knowledge ,
not as a breakthrough Improvement technique.

Critics are frustrated of the poor implementation, big bucks training, highly paid consultants and may be..just may be.. high expectations created from implementing organizations that they saved millions of $$$$.

These are weakness in implementation strategy by the respective organizations. These are not the fault of the Methodology or flaw in Six sigma.

I admit, the missing link in Six sigma is "lack of a standard approach" including BOK - one might call this advantage on flexibility to be optimistic or lack of consistency if critical.

Perception has made Six sigma look like an "Instant pudding". Many organization use the same methodology and tool box and approach and call by different name to defeat such perceptions.

As a note, Lean also has belt certifications (not as popular as Six sigma). Lean learning through reputed organizations are equally as expensive as Six sigma.
People pay bucks to learn Six sigma BB BOK to increase their marketability, enhance their skills. If one is competent enough to take the exam without going the expensive training, they can.

Regards,
Govind.

[Steve Prevette]

Originally Posted by Govind

Critics are frustrated of the poor implementation, big bucks training, highly paid consultants and may be..just may be.. high expectations created from implementing organizations that they saved millions of $$$$.

Well, actually I do have some technical issues with Six Sigma:

1. The 1.5 sigma shift. Proper use of SPC will detect change well before a 1.5 sigma shift.

2. The reliance on numerical targets to determine if you are six sigma capable (anti Deming 14 points)

3. The reliance on short term gains and visible data

4. Elimination of defects does not imply that what you have left is an optimal, good system

5. The lack of system thinking - the stove piping of results without attention to interactions.

6. The reliance on "control" (DMAIC) rather than improvement cycles (PDSA)

These "faults" I believe are inherent to the Six Sigma BOK.

[Jim Wynne]

Originally Posted by Steve Prevette

The 1.5 sigma shift. Proper use of SPC will detect change well before a 1.5 sigma shift..

Yes!! The fundamental fallacy of SS lies in the fact that by emphasizing the 1.5 sigma shift, SS gurus demonstrate that they have no clue about what is actually happening hour-to-hour on a busy production floor. In fact, I'll take it a step further--most times, the fact that something fishy is going on will be discovered before SPC (i.e., control charting) is done. That is to say, operators don't need to plot a point outside the control limits in order to know something's wrong, or headed that way.

[Bev D]

Actually Steve - the technical issues that you have described are the 'invention' of Mikel Harry and are not what six sigma is about at all. (unfortunately, there are numerous hacks who are way richer than you or me who have perpetuated these myths. You are correct that peopel who chooes this path will have great powerpoint presentations but they won't be on the path to six sigma which is really about neve ending evolutinary, revolutionary and breakthrough improvements. The 1.5 sigma shift is never discussed by anyone but PR hacks who really dont' know anything about six sigma. The same can be said about each of your points. well made but only true for those who dont' know what six sigma is - and Mikel Harry never had a clue, just a good marketing idea. For example the DMAIC cycle is a cycle. once you have achieved improvement and put PROCESS CONTROLS in place you start again at the beginnig to make more improvements...just because PDSA isn't specifically articulated doen't mean it isn't done.

[Steve Prevette]

Originally Posted by Bev D

Actually Steve . . .

I agree. If you do go back to what six sigma originally was - the answer to the question of what is the "best" level and variability to operate at when faced with a bunch of specifications, six sigma (a CpK of 2) is certainly a viable and likely answer.

Just as lean is a good answer for some folks as to what is the "best" level of inventory and work in progress to carry. (Tieing this back to the original point of the thread).