Macbeth is a very power greedy person. It is not necessarily his own doing that he is such a ruthless person. It all started Macbeth being power greedy with the Three Witches predictions: "All hail, Macbeth! hail to thee, thane of Glamis!/ All hail, Macbeth! hail to thee, thane of/ Cawdor!/ All hail, Macbeth! That shalt be king hereafter." 1.3.50-54 As soon as Macbeth learned of his future, he began to scheme on just exactly how he would fulfill these prophecies. That is when he decided that he would have to murder Duncan to fulfill the last prophecy. But that...
also murders actually he has people murder Macbuffs family. Macbeth does not murder Macduff, but he does murder his wife, children, and servants. Macbeth can not stoop any lower than the level that he is currently at. Now, it is Malcolm"s turn to want the power of kingship. The reason that Malcolm desires to become king, is because he knows that Macbeth is a murderer and a tyrant. Malcolm feels confident that he will be a fair and just king. At the end of the play when Malcolm comes into kingship, he is a gentle and kind ruler already.