Every line of my recovery code was correct. It failed every single time.

A developer running an automated trading system discovered a critical flaw in their self-healing logic. Despite the recovery code appearing logically sound, it failed repeatedly because the retry mechanism generated non-unique order IDs. Because the broker required globally unique identifiers, every subsequent retry attempt was rejected, leaving positions unprotected. The author emphasizes that structural health checks—which monitor if services are running—often fail to detect logical errors where the system is running but performing incorrectly. The article provides a checklist for robust retry paths, including the necessity of per-attempt uniqueness, the importance of triggering recovery branches during testing, and the implementation of circuit breakers to prevent infinite, failing loops. Ultimately, the author argues that developers must move beyond structural monitoring to verify that their system's internal state matches the reality of the external services it interacts with.