Going to the gym on your lunch hour, running your nuts off, (Literally, not figuratively.) and finding that you forgot to pack another pair of underwear.
Wearing sweaty boxer briefs underneath your uniform isn't the most pleasant experience in the world - especially if you have to go in & out of a freezer for half the night.
Sure, I could have gone commando - but my apron doesn't leave much to the imagination, and I wouldn't want to startle anyone.
They're pretty much dry now, but I tell you - next time I'll have 3 pairs in my gym bag - just to be sure.