Macbeth's demise was due to fate - I would choose character and say that every point that Macbeth had choose to do something terribble so then had , he received some kind of sign telling him to go back but of course he dosent listen to it. The witches had pumoed him up and told him that he would have been destined to rule over Scotland. they play a collateral role you cant blame them for macbeths since, but they still sorta kind did help him push down the path of terriblenes
