Thanks for your questions. I think this questions “What happens when you send food back at a restaurant?” is very important for all like yours.
Here I’m trying to give your answers in brief.

Anything. Nothing. The overwhelming majority of the time, whatever is wrong gets corrected, or at least the attempt at correction the problem is made. For instance, I ordered surf-n-turf at a chain seafood restaurant, steak medium rare. I returned the steak thrice, it was well done, medium well, then charred. Same thing happened at my favorite local chain.

During high school, I worked at a fast food restaurant. Returned food might be eaten by employees and a new order made correctly; it may be corrected, adding or subtracting whatever was wrong; or, depending on where the supervisor/manager was located at the time, who else was working, and an employee’s mood, I’ve seen things done that caused me to stop eating fast food…fake sneezing on it, dropping in on the floor then back on the grill before serving it, and much worse.

I shared my favorite story in another post, I’ll share it here, too. A guy that lived in my dorm used to manage a store for a national pizza chain. He opened one Saturday morning, took an order, made the pizza, then passed it off for delivery. 30 minutes later the customer returned the pizza, claiming it wasn’t what she ordered. “Ma’am, I read the order back to you on the phone and you agreed it was correct”, he said. “ I don’t care, it wasn’t what I ordered, and I want to see the manager”, she responded. “I am the manager, I’ll see that it’s perfect this time!”, he said.

So he took her order again, which turned out to be exactly the same order she placed by phone and received by delivery. He walked to the back, grabbed the dough, and took it to the restroom, where he proceeded to wipe the rim of the toilet bowl with the dough. He placed them placed it on the counter, washed his hands, then made the woman’s order using that dough. He later received a comment card from the customer stating it was the best pizza she’d ever tasted.

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