It's wrong to not tip someone.
Tom is eating out at a restaurant and the kitchen has overcooked his food.
Tom wants to show that he is unhappy with his meal.
Tom points out the problem with his food but tips the server on his way out and later leaves a negative yelp review.
Tom complains about the meal and proceeds to leave no gratuity.
The server is relieved that they got a tip even though the order was messed up.
The server is punished for the mistake of the kitchen staff.