Squeezing an innocuous little blackhead the day before an important event will result in an infection and a massive boil like lump on your face that oozes but doesn't pop and you are left with a cornflake like crust on top of the huge bump.
Whenever you nip out quickly with no make up/wild hair/scruffy clothing etc, you are guaranteed to bump into your ex/your mother in law/the woman your ex ran off with/the girl you hated at school who is now married to a multi millionaire.