· 7 min read
Four Mechanisms, Four Numbers: Why One Reliability Metric Hides the Work
An integration layer that improved API success, end-to-end failure, duplicate results and empty responses did so through four separate mechanisms. Reported as one number, you cannot tell which part earned its keep, you cannot tell when one regresses, and you cannot defend the architecture. Measure each mechanism on its own, and the gap between two of the numbers becomes the most informative thing in the report.