A New Quality Cost Model and the Optimum Quality Level

Since A.V. Feigenbaum (1956) advocated the concept of "quality cost", a number of researchers attempted to use quality cost to determine the optimum quality level. Although there are numerous quality cost models conducted in search of optimum quality level, none has been able to accurately integrate various quality costs to reach a desired solution. In this paper, critics of traditional quality cost model are summarized, and a new quality cost model is proposed which represents the total quality cost as a function of both prevention cost and appraisal cost. While the optimum quality level was traditionally shown as the product defective rate that has the minimum total quality cost, instead, this paper presents the optimum quality level as a combination of both product defective rate and out-of-factory defective rate.