First, my sister ordered a glass of milk. When she tasted it, it was very sour. All right, just a fluke, we decide; so she sends it back and gets a new one. The second one was just as bad. We flagged down the manager because he happened to be walking by and we know him from coming in so often, and told him that this is the second glass of sour milk she's gotten, and that he should probably check the rest of it to make sure it hasn't all gone bad. So he gets her another glass of milk, and tells her that it shouldn't be bad because the carton says it doesn't expire until the 11th.
Needless to say, it was pretty gross. So my sister gives up on the milk and asks for an orange soda instead. Five minutes later, the manager returns... with an orange juice.
The waiter also forgot two of our beverages and brought out my mother's hamburger 15 minutes after the rest (which she then had to send back because it wasn't well done), but the sour milk story was the kicker.