Re-entry, and a headcount you can stand behind

The failure that matters is not somebody sneaking in twice. It is a paying guest holding a valid ticket the door insists is already inside because their exit did not register. That refusal explains itself, offers the override, and never reads as a verdict on the person — while a cancelled or spent ticket is refused outright, with no override, because that is what the door is for.

The count is only true if everybody who left scanned out. A venue that cannot scan people out is put on a policy that makes no claim about occupancy at all, and one untracked staff wristband marks the headline figure as a lower bound. A precise number nobody can support is worse than an absent one.

The list of tickets that never scanned out is what a manager walks the building with. Almost always a missed scan rather than somebody asleep under a seat — but twelve names to dismiss beats a number nobody can check.

An exit the gate did not expect is recorded and never blocked. The count gets reconciled afterwards; the turnstile opens now.