It is my understanding that miscommunication is an issue between players and DMs, especially at the start of games. One assumes one thing, the other assumes another and you're off on a merry chase when someone brings a looney character to your serious business RP game. Or the other way right round. Matters not. The communication is what you should be focusing on. Amazing how many disagreements in games come down to miscommunication. It's the sorting out of those miscommunications that causes the problems. Best to be up front so they rarely happen.