No pasta dish (other than something like tortellini soup) should be served with broth at the bottom. I’m not talking about sauce, like a good marinara, but some watery concoction poured right out of the pot it was cooked in. Served like that, the leftover liquid continues to soften the pasta past the point it was done, turning it into mush.
Similarly, no Chinese food takeout box should contain the oil from the wok. Every commercial kitchen has a strainer or slotted spoon — use it so the customer gets only the solid ingredients, as if they were going to eat it off a plate in your restaurant.
When a water glass is refilled, it should be through the spout that holds the ice back, not over the side of the pitcher so the customer gets more ice than liquid.
No server should ever ask a question — like, “How’s your food?” — at the exact moment the customer has put food in their mouth. In fact, if the server is observant and passes by the table every once in awhile, no question should ever be necessary because customers will get their attention if anything is required.
If a restaurant serves chips — tortilla or potato — it must also provide toothpicks on the way out.