Answer:
i believe that Macbeth has slowly begun to go insane in a way, no longer sound of mind, becoming more evil. At a point, he can no longer turn away from the dastardly deeds he has done.
at the beginning, he is a respected Thane of Glamis, but once he is the Thane of Cawdor, he lets the witches predictions and his own greed poison his mind and uses his power for evil.
i hope this helped!