People have been complaining about the same issues repeatedly to the wise man. He cracked a joke on them one day, and everyone laughed aloud.
Only a handful of them smiled when he repeated the joke after a few minutes.
No one laughed any longer when he repeated the joke a third time.
“You can’t laugh at the same joke over and over. So why are you always crying about the same problem?”
Moral: Worrying is a time and energy waster that won't help your difficulties.