in quick succession on one shift I knocked over a cup full of espresso and mocha, went on to brew a full pot of coffee into an airpot that was already full, then almost fell over while cleaning it up right in front of guests. I've also dropped a full inclusions bin of dried raspberries on my foot, knocked over a steaming pitcher full of milk for a venti beverage, given myself an accidental shower with our blender pitcher rinser (hey, it was new, and literally every one of us did it the first time we saw it apparently by deciding to poke it to see how it worked), sprayed milk in my face when I accidentally started steaming milk in a cup and jerked it back instinctively without turning off the steam wand... and I'm sure there's more. I'm the clumsiest barista in the world, I swear.
those honestly aren't that embarrassing though because I own it. the other night I was writing a cup for a British guest and even though I verified his name with him I thought it was rather an odd name. but Pizza it was, if that was what he wanted to be called. I walked into the back to do some dishes and only then did it occur to me that his name was probably Peter. I could not come out of the back until he was gone because I was so embarrassed. I asked my partner and she confirmed that his name was Peter, but said she figured I'd messed it up so she didn't even call out his name, just handed him the cup. hopefully he didn't read it.