You know that moment right after you wake up from a night of drinking and it takes you a minute to remember where you are? Then it takes you another minute to realize you don't recognize anything? Then it takes you another minute to realize you're Beetlejuice?
You may have to say Beetlejuice's name three times to get him to appear but you only have to tell him leave while you're holding a baseball bat once.
He really is the ghost with the most. The most terrible blackouts.