Unable Jokes

Why did George Washington have sleeping problems? Because he is unable to lie.
Onions are unable to store water inside them because there is always a leek.
Someone stole my cutlery set, but we were unable to identify the thief
It was stainless steel.
"It is amazing how quickly the kids learn to drive a car, yet are unable to understand the lawnmower, snowblower, or vacuum cleaner." – Ben Bergor
Did you hear about the crocodile who was unable to mate?
He had a reptile dysfunction.