Sisyphus

Sisyphus (, "Sísyphos") was a legendary person in Greek mythology. 
According to the ancient story, Sisyphus was forced to roll a big rock up a hill, but it rolled back down and the task was never finished. He was forced to repeat this over and over again forever.The word "Sisyphean", which relates to a task which is undertaken with great effort but is ultimately pointless, is derived from the myth.