My first thought is greed, but seriously I can't understand why? His Trilogy was so far from the book it's near unrecognizable from Tolkien's tale. He added so many characters and sub-plots that more than half of the movies could have been cut. The main themes of the book were destroyed by the change of the Dwarves from exiles to warriors and the change of Bilbo from pacifist in the war of 5 armies to contributing fighter. Lame social justice warrior themes added (feminism/bi-racial love). I could go on, but there is a text limit. In short I feel like he ruined my childhood's favorite story.