after meeting the witches at the begining of the play banquo told macbeth :"oftentimes to win us to our harm...to betray[us]in deepest consequence-"(1.4)how were banquo's words proven true in the end

Ultimately the witches' predictions put Macbeth and Lady Macbeth on the road to destruction. They commit the unspeakable act of killing the King and then his two chamberlains. This is only the beginning of their being betrayed by the witches whose prophecies seem, at first, to be so upbeat and "good."