Been seeing this phrase around, sometimes as a macro, and sometimes as title / caption for a fail picture. Any thoughts?
Now that is not going to be easy to trace…
One of the earliest instances seems to be the 2001 version of Ocean’s Eleven. From Wikiquote:
[in a safe heist]
Basher: All right chaps. Hang on to your knickers.
[He triggers the bomb, and the safe door cracks open. Laughing, Basher dances into the vault – and the alarm goes off]
Basher: Oh leave it out! You tossers! You had one job to do!
I dunno if that can really be stated as the origin, though.