If Mastermind sees “You could not convert your target” then it’ll make him a kill target for Assassin, same with Cult Leader seeing it, he’ll wanna kill them.
If they see “You were Occupied” then they’ll likely think twice about it.
The idea is to avoid being targeted because they can’t be converted.
Look way back at all the times Prince and Sheriff were involved in conversion attempts. They’d get killed off by the Assassin real quickly because the Mastermind would tell them, “Immune to convert” or something.