Things said way too often in the studio, I'll start.

I don't have my own studio but I go to college to learn sound engineering and we record musicians from the music course.

Way too often they say stuff like "It's okay, I don't need a click". Unfortunatly it's the drummers that are worst for saying it.
 
"This drummer fucking sucks." while editing.

Also: "I'm not getting paid enough for this."
 
"Do it again, but this time.. less shit"

I'm a motivator ;)

Also +1'ing at the "It's cool, I can fix it" that Dan put up. So true.
 
"Our drummer doesn't need a kick" or "I've got my amp setting all set up already" or "his vocals sound more aggressive at gigs when he's cupping his hands around the mic than here through this condensor mic" etc...