Finding
An ordinary change can alter a dependency or condition in the pathway, degrading the human outcome while enough technology remains to create the impression that the system still works.
How the mechanism works
Password changes, replacement devices, moved controllers, new workers, altered settings, software updates and changing service behaviour can interrupt relationships that carried the outcome.
Evidence boundary
Outcome Drift is not a label for every failure. Outages, depleted batteries, broken hardware and service closure remain distinct possibilities.