The Punishment Isn't the Effort. It's the Erasure.
The horror of the Sisyphus myth isn't physical exhaustion — it's that nothing accumulates. Every version of human effort assumes progress: you push, and something changes, even a little. Sisyphus's punishment specifically removes that assumption. The work resets, exactly, every single time.
That's the precise mechanism 'Sisyphean' captures that words like 'exhausting' or 'endless' don't: it's not just that a task is hard or long, it's that completing it produces no permanent result at all.

