How do you make a stranger laugh out loud with only your written words?
See, what’s funny to you might not be funny to someone else. Humor is subjective. So far so clear.
But you can force your humor on someone else and literally make them laugh through your live performance. You’ve got the whole arsenal of tools ready to be fired: your words, your voice, your speech (rhetoric), your delivery (deadpan, animated/alive, relatable, confrontational, et al.) your facial expressions (smile, RBF, pokerface, et al.), your body language, your sounds (intentional and unintentional), and the X factors of context, ambience, aura, momentum.
Your story was weak, your punchline didn’t land, your English is not native, your audience doesn’t like you. You can screw all that up but you can get away with it when you use the other live tools you have as an IRL human.