💳 In financial systems, a timeout or an unrecognized response code is not a failure — it’s an UNKNOWN state.
In fintech, the most dangerous failures aren’t system crashes but wrong transaction outcomes that look correct in logs. Treating timeouts or unknown responses as SUCCESS or FAILURE leads to duplicates, wrong reversals, and audit nightmares. The real challenge isn’t calling APIs — it’s deciding outcomes safely. That’s why money safety must always come before response speed.