It is rude to be impatient.
Simon is waiting for his pizza at a shop, and the pizza is taking a long time because it's busy.
Simon wants his pizza.
Simon, knowing it's busy, patiently waits for his pizza to be ready and thanks the workers.
Simon yells and berates the employees until his pizza comes out.
The pizza is delicious, and Simon has a good meal.
The pizza is rushed and not well made, and Simon is told not to ever come back.