They're racing the speed of the flush versus the speed of their piss.

Not even kidding. Source: boyfriends and friends, especially when drunk

it's because the last guy who used the urinal didn't flush it and it smells bad.

When fake 'prez' tells you to flush
twice, thrice, sixteen times
who's gonna Disobey
the fawking Boss?

Besides it's Stinky
if you leave it be
so be Courteous
and Flush, after
and save water
pee with
a Friend.