The Road to "Root Cause": Shop-Floor Problem-Solving at Three Auto Assembly Plants

This paper uses case studies of shop-floor problem-solving at three automotive assembly plants to examine organizational influences on process quality improvement. Three complex quality problems---water leaks, paint defects, and electrical defects---were chosen because they are universally found in assembly plants, have multiple sources, and can only be resolved with high levels of interaction and coordination among individuals in multiple departments or functional groups. The case studies focus particularly on the early stages of the problem-solving process---problem definition, problem analysis, and the generation of solutions---emphasizing how each plant tries to identify the "root cause" of defects. The paper then explores consistencies and contrasts within and across the three cases to analyze the factors underlying effective shop-floor problem-solving. Central to this analysis is the idea that successful process quality improvement depends heavily on how the organization influences the cognitive processes of its members. Problem-solving processes benefit from rich data that capture multiple perspectives on a problem, problem categories that are "fuzzy", and organizational structures that facilitate the development of a common language for discussing problems. Also, when problems are framed as opportunities for learning, the combination of positive attributions that boost motivation and the suppression of threat effects can improve the effectiveness of improvement activities. Finally, when process standardization is understood as marking the beginning (and not the end) of further improvement efforts, the normal inertial tendencies of organizations with respect to adaptive learning can be partially overcome.