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Six Sigma Does Not Equal TCS
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These articles are from the Six Sigma SPC Newsletter and other publications. All articles written by Jim Winings

From the (Jan-Feb-Mar.) 2002 Newsletter


What is the deal? In the beginning, the Six Sigma beginning of course, I don't go that far back, there wasn't any Six Sigma consulting companies. The only politics that you got into was people in your own company that were resistant to change and didn't want to change to Six Sigma. Being resistant to change is human nature, but is a problem even today with starting a Six Sigma or any other program. On top of that, but we believe that the concepts have grown into the proverbial 1000 pound gorilla.

It use to be, in 1985-1990, that Cp was calculated like this (USL-LSL)/6sigma actual. Now they have thrown in Pp and PPk. Pp is calculated like this, I guess, (USL-LSL)/(rBar/d2) by some but apparently not by all. The rBar/d2 is an estimate that is, in part, used with range charts. Where in the world did this start? Who said it and what research have they done? I've been trying to find out but keep running into dead ends. And I believe it was Besterfield in 1987 stated that Cp was (USL-LSL)/6sigma. Regardless of what one may call it, the important measurement is (USL-LSL)/6sigma and estimates are subject to error, so why even use them.

What this really does is make things much more complex than they have to be, which is contradictory to what I was taught Six Sigma is about. Six Sigma is, or at least use to be, about making things simpler and easier to understand. It was about streamlining processes and not doing anything that was non-value added and adding items that were value added. It was about common sense. But now it could be a perception that it is about making things as hard as possible so that you have to hire a team of consultants at $1500.00 per hour to explain things to you. In return, if you are really lucky and you production is already so messed up that anything would help, you will get a return on that investment in about 10 years. You should be getting a return on that investment in half that time. Of course measurement is just one aspect of a Six Sigma program. But it is the one most people have a struggle understanding. And the more complex it can be made by some people or organizations, the better for those people and organizations being hired. Of course not all people and organizations are that way.

For example, I recently got an ad from a Six Sigma organization wanting me to advertise with them. They sent me a courtesy copy of their newsletter. In the newsletter, they were bragging about a conference they had and about the speakers that spoke during the conference. Stating that one speaker from a big company based in Illinois was the star attraction. They stated that this company was a 'industry leader' in Six Sigma. Well, I have talked to some of that big company's suppliers and believe me, they are not an 'industry leader' in Six Sigma, at least not in my opinion.

For openers, the large company's purchasing agents told their suppliers that they would cut cost by 3%. Now this would be OK except that the big company didn't have everyone in their company trained in Six Sigma. They didn't have a vendor council established so that suppliers could bring up problems, usually more often than not due to politics. Without the council in place, at that point in time, they should not have been telling their suppliers anything except here is what we are doing. When the suppliers ask them when the council would be in place, they were just told soon. No time frame of when it would be completed, but the suppliers was told, cut cost, and ah, oh yea, you need a black belt, so train someone. The big company also refused to commit on guaranteeing any amount of business in the future.

It is asinine to expect a supplier to do all that before a council is even established and without committing to giving them enough future business to justify the additional cost of getting 'tooled up'. And it's not like the supplier really had a quality problem. A process engineer told the supplier that compared to other suppliers, they didn't have any quality problems. This is pure politics and a gross abuse of power by the big company's purchasing agent. Of course as we all well know, abuse by power hungry purchasing agents is uncommon. This is not Six Sigma. This it is politics.

Now maybe this big company has since gotten it's 'act' together, but, I bet that whatever person from whatever company this Six Sigma organization could get to speak at their conference would be a 'Six Sigma Leader". Once again, this is politics, and politics costs, it doesn't pay. But only the 'Top Dogs ' can make politics go away, and it seems to not be on their priority list, so we must learn to live with it and deal with it in a elegant manner, and bite a lot of bullets.

Here is something to think about. What would happen if all the companies that are allowed to do 'self-audits' for ISO, QS, or what ever, were not allowed to perform 'self-audits'? What if they were not allowed to from the beginning? Would they have jumped on the ISO and QS bandwagon in the first place? I bet not. Now maybe I have seen 'Conspiracy Theory' once too often, actually I've only seen it once, but let's think about this.

An organization approaches a big company and states, we have a concept to improve quality and we want you to endorse it. Without the big companies endorsing the idea, smaller companies almost certainly will not adopt it even if it improves their profit margins. It is the concept that Quality Is A Necessary Evil. Big company looks over specifications and says, 'OK' but we aren't going to invest the thousands if not millions of dollars it will take for us to comply. It will cost smaller companies less to implement the ideas because they are smaller and are less diversified. Even though in reality, the ratio of overall dollars vs cost may be about the same.

So the big companies are allowed to do self-audits and not required to invest the dollars and time into the concept. The smaller companies on the other hand must in order to continue to do business with the bigger company. The bigger company now has a set of guidelines that their suppliers must follow. The big company does not have to maintain or update these rules, and in theory, their suppliers will have a better product. It is a win-win situation for the big companies and the organizations, but guess whom it is really costing?

Now don't get me wrong. If I were a big company, I would think that it was a good idea too. And I am a firm believer that you must have statistical process control, (SPC), in your production process if you want to reduce scrap, but you have to be able to get a return on the investment. You must be able to see where that return is going to come from. I see companies all the time, even in today's world, trying to inspect quality into their product. It can't be done. Let me repeat that, YOU CANNOT INSPECT QUALITY INTO YOUR PRODUCT! You are already to late by the time you find a defect.

Six Sigma does not necessarily equal TCS, (Total Customer Satisfaction). Sometimes it just means more profit or sales for the company that has implemented a Six Sigma program correctly and nothing to do with customer requirements. Here is an observation that I have made over the last three years.

GE is a Six Sigma company. That should mean that when their light bulb packages say the bulb will last 1000 hours, there is a very high likelihood that you will get no more than a few more hours over 1000 hours as the package states. If it's less, they will be in trouble with the U.S. Government, so companies typically make sure that their products do at least what the package states by a certain percentage. GE light bulbs usually cost more than the no name generic brands, but because the no name generic brands may not and probably do not use SPC, let alone apply any Six Sigma concepts, you get many more hours from the no name generic brands than from the GE bulbs. This is because they still must guarantee at least the number of hours that their package states, but they have less control over the production process. Ergo, to insure the minimum hours they must add 10, 20, or perhaps 30 percent more to the life of the bulb, depending on their production line and materials, etc. whereas GE may only have to add 5 percent or less because of having a very tightly controlled process.

Even if the no name generic brands used just a standard SPC program with a 3 sigma design margin, it is nowhere near as tight as the 4.5 sigma design margin, but it would be much more cost effective than no control at all because they may sell more units.

The last time I was in Thomas Edition's summer home in Ft. Myers FL, it was about 1972, there were still light bulbs burning that was made my Edition. So it is technically possible to make standard incandescent light bulbs to burn for about 100 years, if they did though, you would only have to replace a bulb if you broke it. This would make a light bulb cost about $100 each, so there has to be a wear out some place. While Edison's bulbs were not very bright, they were still glowing. I reckon it has something to do with the tensile strength or thickness of the filament or the inert gas. But, I was changing GE light bulbs it seemed like every 6 weeks or less, and of course they always stopped working at night, when the stores were not open and when you need them the most.

So I now only have 3 standard incandescent light bulbs. One bulb over the stove, one bulb in the hallway, and one bulb in the bathroom. I switched to fluorescent bulbs everywhere else. I have had to change only one fluorescent bulb in 3 years, and I am saving energy too. It was a real good Six Sigma solution to the problem, and I didn't even have to spend thousands of dollars to do it.

Update: It seems that at some point after this article was published, GE changed their light bulb boxes to indicate that the 1000 hours is based on average usage defined as 2 hours per day. Apparently someone at GE decided that 2 hours was an average.

According to the A.C. Nielsen Co., the average American watches more than 4 hours of TV each day. I'm assuming that the majority of the population of this average is based on more nighttime viewing than daytime due to most people, at least when the survey was taken, had daytime jobs. No doubt GE knows this. I have my kitchen light on for more than 2 hours a day, on average. I do cook, bachelors may have a lighter usage load, but I don't see a family using less. The ONLY room I may use a light for 2 hours in, on average, is the bedroom.

So by using an unrealistic average, they could degrade the reliability of the filament, thus reducing costs, and achieve six sigma goal. Wonder if this occurred when Jack Welch was in charge? 

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Last Updated: Saturday, 15-Apr-06 19:47:38 PDT