When you have an obnoxiously affectionate cat and you teach him to request pets politely.
Ok but real talk how did you get him to do that because I have a cat that is so aggressively affectionate that we refer to him as the slut.
I spent several weeks shaping the behaviour. I would sit in a way that wouldn’t let him jump in my lap, and I’d hold out a hand and pet him with the hand. Then I put my hand on the arm rest. Eventually Burdock stood up to follow the hand; he got pet as a reward. He quickly learned “stand up = pets”.
After a few days of that, I stopped responding to the standing so he started doing things to try to get my attention. One of those things was reaching up with a paw. If the paw was gentle, he got pets. If there was claws, I removed my arm from his reach entirely, which was the opposite thing of what he wanted. So he quickly learned to be gentle.
One day I was distracted and didn’t notice the paw, so he licked me. He got LOTS of pets for the lick and that became the full, complete behaviour.