You love it when you crit a gym leader's head, but you hate it that other trainers seem to crit you more than you crit them. You hate that you always seem to crit something you want/need to capture, but love it when you crit with your last; weakened pokémon and pull a victory out of thin air.
I hate it when I fail to crit twice in a row with 70+% crit odds on an enemy that I absolutely need to defeat and a single cent would down, but I love when a 1% chance activates on a tough enemy and I get to, at least, avoid a counterattack.