Delivery drivers that can't go to the right address.
It's a huge site here - something like 170 people on site - with offices, a warehouse and ~100 workshop bays - so people often get a bit lost. It's a little tedious, but I get it.
He's driven past out our service department, main reception, and receiving/dispatch warehouse and come across my office.
"Hi, I've got a delivery for the service department" (Literally the first thing he drove past)
I have a look at his delivery form to see who it's addressed to so I can direct him accordingly.
"Ah, there's your problem mate - you're looking for number 320-328 (street number), we're 392".
He gives me a look of disgust, and ambles back to his truck.
(My brain) FFS, you had one job Mr. Delivery-man,
one job...