Have you played Mafia where some roles have one-time use protection?
When the Mafia knows for sure that there is protection and it needs to be removed, they simply don't want to do it; they ignore it and choose another target, guided by the same randomness or some assumptions.
There is no desire to spend a precious night, which can also fail due to a block/protection/healing, on trying to break through.
Ничто не возникает из ничего и ничто не пропадает бесследно.
Если где-то чего-то убудет, то в другом месте добавится.
(Закон сохранения).