I've never understood why men stand to pee in a toilet. I can understand it for urinals and trees, but why toilets?
If you want to know why it's a bad idea - drape a couple of sheets of paper over the edge and see what happens. It gets splashed - back out from the toilet. And that splash doesn't stop at the rim - it goes over the floor (and that's often carpet remember), the skirting, the pipework, your shoes.
So, chaps, WHY do you do it? Just sit down and aim in - or learn to wipe up after yourselves ffs.