Whenever I try to use a urinal, I never have to go as much as I thought I did, and nothing comes out. And then someone walks in the bathroom, and I'm just standing there, clearly not peeing, and it looks weird. So I usually don't take that risk anymore.
Something I dislike: Guys who bypass all the urinals to go stand up in a stall and don't lift the seat. If you are a female reading this topic and you are upset that some guy somewhere leaves the seat up, be thankful that he lifted it in the first place, because that is what really matters. We have a bad habit of overestimating our aiming abilities. And then we just leave it there for someone else to clean up. Back when I was in a guys' dorm with a communal bathroom, a lifted seat was a welcome sight because it probably meant the seat was relatively dry.