There have only been a couple of times when I stiffed a waiter/waitress. Both times they deserved it, IMO.
Once was in Las Vegas and when the check came it had a $5-something charge on it that we couldn’t figure out what it was for. Everything else was accounted for. I don’t know if the $5 was the “tip” already figured in or what, but every time I tried to flag down the waiter he ignored me. Finally just left the exact change and walked out.
That particular restaurant also had the distinction of serving the saltiest food I’ve ever tasted.
Just make sure to check (twice!) and make sure you don’t leave anything behind. Don’t go back either.
My husband is known for tipping our servers well. One time our service was so exceptionally lousy that he gave the tip to the busser who was really helpful, and gave nothing to the waitress.