Surprise Party Arrival Policy

One thing you can't be late for is a surprise party for a friend. You never want to be that guy who your friend sees when he's walking in for the surprise. Even if you're only a few minutes late and there before the guest of honor arrives, you can throw things off by walking in and getting everyone's hopes up only to let them down. Then they begin to subconsciously make a mental association with seeing you and being disappointed, so the best idea is really to arrive well in advance for these things.