There are a few core problems with videogame movies ...
First off, (much like books) videogames are much larger experiences than movies and are much more personal in nature so it is difficult/impossible to adapt them to be as large and meaningful to individuals as the videogame was. When you end up having a game series (like Mass Effect as an example) that has multiple 40 hour games each being filled with countless decisions and multiple ways to play through it, how do you filter this down to a 2 hour experience?
The bulk of story elements that can be taken from videogames to make a movie are "after-thoughts" (for lack of a better word). Many/most major videogame franchises date back to primitive hardware and the game was designed entirely with the gameplay elements in mind; and characters, plot, and environment were afterthoughts or could have been created because of limitations in the hardware. In Super Mario Brothers (for example) Goombas were originally supposed to be chestnuts, but because of the limitations in the hardware everyone saw them as mushrooms.
Finally, Hollywood has lost the ability to actually effectively tell a story. How many successful, critically acclaimed, or popular movies that come out of Hollywood are original creations; and not the adaptation of a comic book, novel, TV show, remake of a movie, or a remake of a foreign film? Of those that are "original works" how many do not blatantly rip off storylines or plot elements of popular or successful movies? Don't get me wrong, I accept the argument that all stories have been told before and you can show similarities in all stories to previous stories that have been told forever; but what I'm talking about is movies that (seem to) take a script written a few years ago, rename a few characters and update the slang to re-release it as a new movie. This is such a problem for videogames in particular because you have to have a good understanding of storytelling to take a format as unconventional as a videogame and translate it into a movie; and the writers in Hollywood simply aren't that good.
