Yea leaving when you should can be a hard thing to do at times, but you can do it if you set your mind to let go of the game.
All of th original post i like except that if you are playing live, and say you are playing $1-$2 NLH and your win goal is like $500. If for some reason your table is crazy you may make this within the first 30 minutes, or less, if you are lucky. I suggest that you do not leave the table right away- 'hit & run" can cause all sorts of issues, to the point of being beaten up, banned from a home game, or having players refuse to play with you (this one can happen online too except at Bovada
) so just be careful. If you hit your win goal early just fold for an hour, have a drink or two, then leave.