2020 Issue

40 Dr. David Wetzel Dave Wetzel is a Lean Six Sigma Master Black Belt with over 30 years of work experience in the industrial, service, and public sectors as a process improvement engineer, facilitator, trainer, and course developer. He has a Ph.D. in Industrial and Systems Engineering from The Ohio State University, an M.S. in Engineering Management from Rensselaer Poly- technic University, and a B.S. in Chemical Engineering, also from OSU. Dave has held several different ASQ certifica - tions: quality engineer, black belt, and quality technician. Production, viewed in this way, is either on (100% good) or off (100% bad). We use the following questions to explore this widely-held view of production: • Is there a “happy” zone? • Is there a sense of loss all the time? • Which Family of Measure is illustrated in the figure? • What question does this metric answer? There is absolutely a “happy zone” when things are deemed 100% good. No process improvement efforts will be taken under these “happy” conditions. There is no feeling of loss under these conditions. When the product or service is deemed bad, a feeling of 100% loss exists, and problem-solving techniques are employed to regain control. This feeling of 100% good or 100% bad is bino- mial. It is a productivity metric. What we produced is either good or bad. How many good or bad? Yields are either calculated directly from counts; or measured, disposi- tioned, and then totaled as good or bad. Two problems occur as a result of this version of process management: (1) productivity yield metrics are used to monitor the process, masquerading as quality metrics; and, (2) problem solving is the predominant method used to “improve the process” when things are bad. An alternative to this process management strategy is illus- trated in Figure 3. and process management indices. The idea is not to reach an arbitrary goal, but to continuously improve the process. Two profound differences occur as a result of this version of process management: (1) quality indices are used to monitor the health of the process (with throughput, yields, cycle time, costs, and other metrics), and, (2) continuous improvement is the method used to improve the process. To appreciate the difference between the two compet- ing views of process management, one would need to understand all the organizational factors that promote the traditional productivity-focused step function version (the “hero” mentality, competitive reward systems, discomfort with statistics, overreliance on audits and inspections); a discussion of which is well beyond the scope of this article. Need for Order Winners Most companies operate on a half-set of metrics (produc- tivity and financial), sprinkling in some operational-level timeliness indicators, but mostly excluding quality alto- gether. They think they are measuring quality, mostly with yields, and then wonder why customer complaints and war- ranty costs are rising, while market share and repeat busi- ness are declining. The ever-increasing presence of global competition is not going away. Our needs are urgent: the need to stop degrading rich timeliness and quality metrics into simple percentages; the need to differentiate between productivity and quality; and the need to develop leading indicators of quality. Family of Measures is a tool that helps address these needs through the reexamination and delin- eation of metrics into distinct metric families. References Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK Guide), fourth edition. Newtown Square, Pennsylvania; Project Manage- ment Institute, Inc., 2008. Stock, J., and Lambert, D. Strategic Logistics Management, fourth edition. New York: McGraw-Hill Irwin, 2001. Deming, W. Edwards. The New Economics for Industry, Government, Education, second edition. Cambridge: MIT Press. 2000. Figure 3 Alternate View of Loss Let us apply the same series of questions. There is no “happy zone” because the process aims to meet nominal. The odds of being exactly on nominal are small; thus, a sense of loss always exists and increases as we stray from nominal. This feeling leads to continuous process improve- ment efforts to center the process better and continuously reduce variability. Most importantly, improvement efforts continue even when the product or service is within tolerance (deemed good). The primary question is, “How good or bad?” This question is a true quality metric. What we produce may be either good or bad, but we also want to know the degree of goodness or badness or to answer the question, “How well?” To do this, we measure variability, central tendency, and the stability of a process. We compare our process to customer specifications and calculate process capability