The following two quotes are actual interview transcripts developed in fieldwork carried out in an automobile company in the United States. The managers, from two different component plants in the same division of the company, describe why the yield of their lines was persistently low and why it had been so difficult to get process improvement programs off the ground (Repenning and Sterman 1999): In the minds of the [operations team leaders] they had to hit their pack counts [daily quotas]. This meant if you were having a bad day and your yield had fallen ... you had to run like crazy to hit your target. You could say, "You are making 20% garbage, stop the line and fix the problem," and they would say, "I can't hit my pack count without running like crazy." They could never get ahead of the game. - Manager at Plant A Supervisors never had time to make improvements or do preventive maintenance on their lines ... they had to spend all their time just trying to keep the line going, but this meant it was always in a state of flux ... because everything was so unpredictable. It was a kind of snowball effect that just kept getting worse. -Supervisor at Plant B Develop a single causal diagram capturing the dynamics described by the interviews. Name your loops using terms from the quotes where possible. Explain how the loops capture the dynamics described. Build your diagram around the basic physical structure shown below. The Net Throughput of a process (the number of usable parts produced per time period, for example, the number of usable parts produced per day) equals Gross Throughput (the total number produced per time period) multiplied by the process Yield (the fraction of gross throughput that passes inspection and is usable). The remainder, Gross Throughput (1 - Yield), are defective