Definition
A measure of how often humans must step in to compensate for system shortcomings — manual reviews, ad hoc patches, or empathy work. It counts how often the system draws on the human subsidy. A rising index shows a system that runs on extraordinary effort, and makes the case for investing in controlled ways to degrade.
Targets & breach behavior. Measurement window: weekly median; monthly review. Target / floor / ceiling: target ≤ 5% of cases, floor 10%, ceiling 20%. Owner: traceable ownership (required). Breach action: expand graceful degradation, add staffing, or halt automation in the affected class. Public surface: receipt + time transparency that flags human review and decision artifact.