rollback

Reported from JPMorgan's MLE loop, and graded on one distinction most candidates miss: rollback is a capability you build before the incident, not an action you improvise during it. The pointer-flip mechanics, the auto-trigger debate, and when rollback itself is unsafe.

An ambiguous, time-pressured staff scenario: the signal is soft, labels won't confirm anything for weeks, and rollback itself has risks. The decision framework under uncertainty, when to revert on a proxy, and the remediation for decisions the bad model already made.