how does changing the plot of a movie make it more interesting?

Question by Mia T: how does changing the plot of a movie make it more interesting?
How does the changing plot of a movie make it more interesting? does it make the audience more engaged or distracts them?

Best answer:

Answer by My Backdrop «Under Construction»
It usually means the producers or the director felt there was not enough or it was too short. Charlie and the Chocolate Factory is a perfect exampl. The whole “I hate my father so your parents must be bad too so I can’t let them in my factory.” was either for length or because they felt there was not enough.

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