Failure mode
Metric Definition Drift
A gradual change in metric meaning caused by hidden logic changes, shifting business rules, or uncontrolled local variants.
Domain: semantic-reliabilityDomain: change-reliability
ARF layer: semantic-integrityARF layer: analytical-explainability
Signals
- stakeholders notice that the same KPI no longer means what it used to mean
- historical comparisons look wrong after a model change
- local fixes create multiple partially overlapping metric variants
Why it matters
Metric drift undermines both trust and explainability. If the meaning changes quietly, the platform cannot give stable answers and leaders cannot reason cleanly about change over time.
Prevention patterns
- canonical metrics with controlled variants
- version notes for semantic changes
- metric ownership and change review tied to release workflows