It goes deeper than that. For example if you wal into the bathroom from the left and there are 5 urinals, but 3 are in use, like this (how they should be, where X represents a urinal being used and U represents an open urinal):
X U X U X
then the proper urimal to use is always the one closest to the door, so it would be like this:
X X X U X
otherwise you are a total creep.