It was Sisyphus who struggled mightily against the odds, pushing a boulder up a hill. As he pushed, it rolled back. He suffered as penance for an outsized ego and deceitfulness.
Working against the odds can bring the greatest success when and if you do succeed. Sisyphus does not succeed. He is being punished by the gods for behavior unbecoming. As a response to his hubris, he will push in one direction, and have the large rock slide back down on him for all of eternity.