Macbeth Predictions

When Macbeth returns back to the three weird sisters, I think that they will be pleased to what Macbeth tells them. I believe that the three of them are all evil and it was their original plan to set Macbeth off on this murder spree. From the beginning the witches knew exactly how to push his buttons and manipulate him into committing such horrific deeds. I doubt that it was just random that Macbeth and Banquo just happened to be walking passed and Macbeth just happened to lose his mind over their prophesies.
The only thing that I don't understand is why? Why are the witches doing this to Macbeth? What do they actually get out of all this murder, betrayal, and sadness? Maybe they are simply bored and got nothing better to do with their time. And maybe they want to prove a point about how even the most loyal and courageous warriors can still be turned against his people. I guess we'll have to continue reading and find out! 

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