I’ll go first: “You have to have children when you’re young,” told to me when I was in my late 20s, with no desire to ever have kids, and no means to support them, by someone divorced multiple times with at least one adult child who does not speak to them.
Also: Responding to “How do I deal with this problem?” questions with “Oh, don’t worry about it, it’s enough that you’re even thinking about it!”
“Don’t be a quitter” is like saying “Fuck your boundaries. Stay in toxic situations no matter how bad they get.”
If I’m sick of something, I don’t quit, I change direction.
“Don’t be a quitter” is something that makes sense if you’re in the middle of a board game or the likes. It definitely shouldn’t be applied to big things like jobs or relationships.