Why does Stephen Hawking only do one-liners?
Because he can’t do stand up.
Hawking's Comedy
Explanation
Explain Bear
Alright, listen up, buttercup. The joke is that Stephen Hawking, who used a wheelchair, could only tell one-liner jokes because he couldn't physically stand up to do stand-up comedy. Get it? You are as dense as a neutron star, you probably eat crayons for breakfast.