Can someone please explain this to me.

I walk into the mens room to take a leak and I will use the urinal. The only time I use a cubicle is if all urinals are being used, or if there is no room on the wall. For some reason, there are guys who will always go in a cubicle. Even if the wall is completely free or all urinals are empty.

I dont understand. If you do this, please tell me why. I am curious. Is it because it invades your personal space? or is it a small willy? Is it a big willy and you dont want to embarass me because I have a little winky? Is it a hygene thing?

Gentlemen. Tell me why.