Described is a technology by which software instrumentation data collected during software program usage sessions is analyzed to identify potential problems with software program usage, such as based on frequency of problem occurrence during the usage sessions. Reliability metrics may be calculated from the information. Failure data additionally collected during the usage sessions may be accessed to derive details that correspond to the potential problems. In one example, the information may be analyzed to determine which alerts and/or asserts occurred most often, and/or to determine a relationship between user interface control operations (e.g., clicks and usage of commands) and alerts or asserts.