Extremely annoying. I don't have OCD (that I know of) but I have a lot of 'habits' - nail biting, picking at the sore on my wrist where my cheap jewelry has irritated, twirling my hair. I get super annoyed when people, especially family, tell me to stop biting my nails. I've tried. I even got into painting my nails to make them look pretty so I wouldn't want to bite them. It does not help. It's not that I want my fingers to bleed or my nail beds be wrecked, but I just. can't. stop.