Rule #1 of course being "users lie".
I'm installing a printer in the Endoscopy Dept. at the local hospital, and having a hard time finding the right port. Most of the rooms aren't signposted, and the ones that are marked aren't numbered in any logical order, so I stick my head through a door that doesn't have any medical equipment inside and ask for directions.
"I know exactly where that's going!" bellows the helpful user joyfully. "$BOSS_LADY told me to expect you!"
( Awesome. )