Why rotations drift without a record
A rotation is vulnerable in a way that a daily task is not. If a daily item is missed, it is noticed the next morning. If a floor's turn in a fortnightly rotation is missed because the level was inaccessible or the attendance ran short, nothing looks wrong at all, and the floor simply waits another two weeks. Repeat that twice and the interval has quietly become six weeks.
The drift is rarely deliberate and almost never visible in the moment. It emerges months later when one floor looks noticeably worse than the others and nobody can explain why. A dated record prevents it entirely, because a floor that has not appeared in the record for two cycles is obvious to anyone who looks at the page.
