Really agressive shortboarders who are surfing like they have something to prove. You can just tell by the way they paddle and get all big and have that look.
Or people who get all agressive and paddle for a wave only to back off last minute. Many waves wasted by people calling you off then bailing. If I see a guy blow a wave once or twice he cant be trusted with a good wave hell probably waste another one. There arent that many good waves and its sick when people get good rides but when they fall on every wave thats it for them.