Why must book characters change for the movies?-Murrhee

Continuing on with my Twilight craze, I would like to start on the subject of its characters.

Okay, the movie is a fairly good representation of Stephenie Meyer's written Twilight. Sure, time frames have been switched and minor details taken out to conserve time. The running time for the movie is 120 minutes (two hours) and most teenagers don't like sitting much longer than that. However, this was like a supernatural Titanic, so maybe the tendency to fidget after sitting for two hours could have been curbed.

While I can dismiss the changes in plot to allow for time, I cannot dismiss the change in some of the characters for the movie. All of Meyer's characters are Caucasian (at least the main ones that I can remember). However, this is not the case in the movie. Perhaps the director, Catherine Hardwicke felt the need to meet that usual status-quo and implement African Americans (there's two in the film) and an Asian into the mix (that still leaves out plenty ethnically, however).

It is within my personal belief system that a character should never be compromised if the character is based from a novel first. The characters of Laurent, Eric, and Tyler were all changed in Hardwicke's Twilight. Laurent, played by actor Edi Gathegi is NOT a serene looking African American with dreads down to his waist. He is a blond with hair down to his shoulders and has a far more omniscient presence than he does in the film.

The character Eric Yorkie--played by Justin Chon--while still acting greatly the same as in the book, is an Asian in the movie. Tyler Crowley, played by Gregory Tyree Boyce is the last of our ethnically-changed characters, who acts greatly the same in the movie, as he does in the book but is again, of African American decent.

Besides aesthetics being changed, personalities change too (refer back to paragraph four). Rosalie isn't nearly as beautified as Meyer's makes her in the book and she comes off as a total bitch throughout the movie, a reason never being given as to why. Rosalie's bitchiness is explained in the book as jealousy toward the main character Bella.

I could go much farther with this but I've tortured you for long enough. My main point having already been made prior, I will reiterate it again: The characters of a movie, if based from the characters of a novel, should exactly mirror them and should not be changed for a director's personal agenda.