Some people think that quality metrics and in particular defect metrics don’t help us to understand the root cause of problems. The assumption is that metrics only tell us the magnitude of the problem. If you concentrate on defects and their count, or removal rate, then it’s easy to see how this can happen. However, quality metrics can tell us much more about the root cause of problems in our development and QA process than you might think. You can identify when the defects occur in terms of time, and in terms of process. You can also identify where they occur or who causes them. You may even identify that they occur most frequently during a certain point in the process and by a certain person or group. The point is not identifying a person or someone to blame, but pinpointing a weakness in the process. Once you identify this process weakness, then you can quickly focus on it and determine why it happens. Depending on how you code or categorize your metrics (attributes) and the methods used, there is a wealth of other information you can get other than counts such that root cause analysis is possible. We call this whole process a Quality Process Analysis or Assessment or QPA.