Staleness

Staleness is the gap between when something was observed and when someone is reading it. Every check result carries its date for this reason, and every statement shows when it was last refreshed.

An app that passed a check in March may have lost a header in April during a refactor nobody thought was risky. The observation was true. It stopped being true. Both facts matter to whoever is reading.

This is also the argument against badges. A badge is an observation with its date removed, which is exactly the part that decays. A dated line ages honestly: a reader can see it is four months old and decide what that is worth. Release Assurance exists for teams who need that gap kept small.

No incident in the library maps to this one yet.