Never, that I can remember. If the food is not good, which rarely happens, I will let them know that I know it’s not their fault. If I want something, and I’m waiting for them and they don’t come over, I will get up and get it myself, if possible (napkins or whatever), or I’ll get up and innocently ask a manager for it and he’ll get them hopping. That’s usually embarassing to them, to have their customers up on their own, which isn’t supposed to happen.
One time I was in a restaurant and ordered dessert. The waitress brought a tablespoon. I asked her for a teaspoon, smaller spoon. Who can eat with a tablespoon? She said “those are the only spoons we have.” I didn’t believe it. I asked her “You mean the coffee is served with a tablespoon?” She said yes. Makes zero sense and since it was hard to believe, I had to verify. I asked another waiter and they brought me out a teaspoon. He said they were all being washed at the time. Our waitress lied. I don’t think her tip suffered because I was with other people and we split the bill, but on my own, her tip would have suffered.
I read that the hard part about being a waiter is that you get blamed for everything: the food is bad, the food takes too long to cook, etc. On one of the few occasions when I returned something, I made it clear to the waitress that I know it’s not her fault. I went to a diner and ordered blueberry pancakes, and they were regular pancakes with a glob of blueberry glop, like canned blueberry crap on top. Gross. The wait staff is always appreciative when you let them know it’s not their fault. I told her “I know you didn’t cook it, but this is gross.” She was very understanding.