Pre-money-bubble I never look at the standings, why would I?
On the money bubble, if I'm short-stacked I constantly check the leaderboard because that is critical information for my decision-making .
And also, if I'm one of the big-stacked chip leaders near the bubble, I'm also constantly checking the leaderboard because now I want to be applying maximum pressure to the shorter stacks at my table and so I have to know where those players stand in order to anticipate what they might do against me.
Once we're in the money, its not important to check the leaderboard, but I often check it anyways just to see how much profit I've earned so far. There's no reason to do this, I basically only do it because I'm bored with folding and because it makes me feel good to realize I made another cash.
tl;dr: the only time I consider it important to check the leaderboards is at the money bubble, all other times its merely for curiosity and out of boredom.