Conversation so far:
Who has to push the rock up the hill
Sisyphus, king of Ephyra, was punished to roll an immense boulder up a hill only for it to roll down when close to the top, repeating this action for eternity.
Why was Sisyphus punished to push the rock up the hill
Sisyphus was punished for his self-aggrandizing craftiness and deceitfulness.
What person chose Sisyphus's punishment of pushing the rock up the hill
Zeus made King Sisyphus roll a huge boulder endlessly up a steep hill.

Question: why Zeus
Self-contained rewrite: Why did Zeus decide on Sisyphus's punishment