What is a go/no-go readiness board?

A single page listing every opening-critical item across the workstreams, each with an evidence-based status — where done means demonstrated, not claimed. The rule is set in advance: the predefined critical items must be at done before doors open, and if they are not, the date moves rather than the standard. It exists to take opening-day judgement calls away from exhausted, emotionally invested people.

From The 45-Day Pre-Opening Discipline: What the Last Six Weeks Decide — the full reading, with the method behind this answer.