I think we all use cliches in WvW, whether in Voice Comms, or in squad chat, to help rookies learn the game, or just to express frustration.
Below are a few of mine.
What are your favorites?
Don't be a Bag, Stay on the tag.
Join Voice Comms for the jokes.
Have Fun. It's a game.
Put away your mini.
You have 2 ears, and one mouth. Listen twice as much as you talk.