It is near impossible to say anyone is the best director of all time but i can say that Martin Scorsese is the most Consistently great. If i were to list all the great movies he has made I would have to list almost all of them, and it is defiantly debatable that listing all of them would be justified. From Mean Streets to Hugo, Scorsese has proven to be a master of cinema and the greatest story teller of our time. Anyone who loves film loves Scorsese.
Just watch this
The most successful director of all time not just a incredible director but a outstanding business man. The only bad thing that he ever made was unintentional, that was a Hollywood based around franchises and merchandising. Without him we would not have the Hollywood we know today whether you view that as a good thing or a bad thing you can not blame him for making movies that were successful.
There is no doubt James Cameron is a incredible director his ability to innovate and to capture the essence of imagination is unmatched, but personally i feel he is just not a great writer and that's why his movies like avatar are criticized an way he is overlooked as the amazing director he is because the poor writing drags the quality of the movies down, but he truly is one of the top ten directors alive, but just an okay writer.
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