I ordered my macaroni and cheese and the guy behind the counter told me that I'd have to wait about 15 minutes because they were all out (usually, when they have some available, it's ready pretty quickly, especially when the restaurant isn't busy). I still really wanted some, so I paid for my drink and was told that they would tell me when the macaroni and cheese was ready.
15 minutes pass by, I'm told that my food is ready, and I pay for my meal and get a buzzer. I wait another 5 minutes or so before the buzzer goes off. When I go up to the counter, I'm told that no, they actually did NOT have any macaroni ready, and that I'd have to wait ANOTHER 15-20 minutes for more to be ready. THEN WHY DID YOU TELL ME THAT MY FOOD WAS READY AND HAVE ME PAY? I couldn't wait ANOTHER 15-20 minutes for my food, because then my friend and I would be late for the movie. So I ordered my usual (I swear, these things only happen when I deviate from what I normally do), and they didn't charge me. I mean, I'm glad that they were apologetic, but I think that they could've improved in the communication department. I've never had bad service here before, though, so this could just be a fluke.
TL;DR: After waiting 15 minutes for my meal to be ready at Panera, I was told it was ready and then paid for it. I was then told that it wasn't ready and that I'd have to wait another 15 minutes, which I didn't have because I was pressed for time.