Macbeth is the protagonist of the play, even though he is not a good or sympathetic character. His ambition to be king at any cost drives the action of the play. From the beginning of the play, Macbeth is unrelentingly ambitious; nothing that happens to him, up to and including the death of his wife, can thwart him in his quest. Due in part to the Witches’ prediction that he is destined to be king, Macbeth believe he is justified in committing murder to satisfy his ambition. Although Macbeth achieves his goal of becoming king, his ambition is never fully satisfied, as he spends the remainder of the play trying to defend his throne. At the end of the play Macbeth learns the futility of his quest as he understands the true meaning of the Witches’ prophecies. But his knowledge comes too late for him to correct the error of his ways, and at the price of everyone he loves, as well as his kingdom.