Reliability testing for customer satisfaction attributes

When reliability testing is performed, the focus is often on engineering metrics that are of interest to the design engineer. This can result in missing failure or degradation conditions that affect customer satisfaction with the product. There is a need for a structured approach to plan the test, engineering metrics and measurement system (instrumentation) on product or system attributes that relate to attributes that affect customer satisfaction. This paper shows how a simple needs-metrics matrix (a common element used in QFD) can be expanded to serve as a structured tool to establish laboratory test instrumentation for objective measurements in a reliability test. It also shows how the matrix can be further expanded to include results of interim subjective evaluations. This expanded matrix can then be used to readily relate the results of reliability testing as well as subjective testing to potential impact on customer satisfaction.