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There are some instances where the physical attributes of a product completely conform to the design specifications and the performance of the product displeases customers. For example, transmission components were manufac­tured by a Ford plant and a Mazda plant in the U.S. Both plants produced the components to the design specifica­tions and later all transmissions were assembled at a Ford plant. After the cars were used for a period of time, Ford received complaints from customers, regarding the perfor­mance of the transmissions. An investigation revealed all of the rough-shifting transmission's components were made at the Ford Plant. [8] See Figure 6.

As a result of this situation with the transmissions, Collins and Huge point out that conformance to specifications (a la zero defects) may be inadequate. Collins and Huge assert the reduction in variability is the goal. [8] If it is proven the design integrity is acceptable, then it is difficult to argue against the study and elimination of variation within the operations, even if the operation contains poka-yoke functions.

Based upon variation's contribution to inferior product performance, the settings of the poka-yoke implements should be dimensioned to limits tighter than the upper and lower control limits or the design specifications. This will facilitate feedback to the operator or equipment when the operation nears or exceeds these control limits. This ap­proach would reduce variation by virtue of disallowing it without any reliance on human judgment.

However, if the source of variation is the machine, these poka-yoke devices would constantly be shutting down the equipment and production would decrease. If the perfor­mance of the machines cannot be improved to minimize the variation, then it is obvious the wrong machines or pro­cesses are employed. Continuing the study of variation would do nothing toward improving the quality. Specific technical solutions with the equipment or operating proce

dures may offer the root solution to the problem. Or the outright removal of the equipment from the process may be the only solution, if the company wishes to continue participating in the market place. Of course, it is better to produce a few good parts, as opposed to a large number of bad parts. Some people argue this point, by qualifying an ability to sell all of the "bad parts." In this case these people ask, what is the problem? This short-sightedness is one example of why many US companies are in decline.

Finally, if the integrity of the statistics is in question, whereby the measurements are not recorded in the pre­scribed, scientific manner, then the roughness in the transmissions could be due to reasons other than variabil­ity. If the measurements are recorded in a manipulative manner, it is possible some parts were manufactured outside the prescribed tolerances. This, of course, could very well lead to "rough shifting" transmissions.

ZQC advocates the equipment and processes be designed to remove all human judgment from the process. This is not a negative statement against humans. After all, hu­mans design the products, processes, and equipment and select the markets they serve. Mundane activities, such as monitoring and recording measurements, especially in a repetitive manner encourage distracting thoughts. ZQC recognizes this human shortcoming and thus removes reliance on human judgments from the process. This will enhance quality.

It is important to recognize the strengths offered in TQM and build upon them in your organizations. Conversely, it is just as important to recognize the weaknesses in TQM and ensure these points are not part of your plans and operational procedures.

It is important to build upon those that preceded us. The teachings of Deming, Juran, and Shingo are not to be discounted, but to be imploded and then expanded to yet newer and more accurate philosophies. At some future point, these improvements will be challenged by yet more improvements, as the cycles should continue.