Mine all leak eventually.
The female leaks gradually through abuse. Getting dropped (even with the ball fitted), the edges get bashed and a little jagged, and the spring loaded ball bearing joints get a bit clogged with dirt from time to time. The male part always ends up kicked to bits (even with a ball fitted) leaving jagged edges which water eventually seeps through.
I'm not complaining though, they're not meant to last using them the way we do. I change mine about 4 or 5 times a year.