This was the year the Academy expanded the number of Best Picture contenders to 10, largely to give more popular films a chance. Yet James Cameron's Avatar, history's biggest box-office performer, lost the top prize to The Hurt Locker, the lowest-grossing movie to win Best Picture in recent times. Here's five theories on why Avatar got left in the dust:

1. Actors hate computer graphics
Actors constitute the Academy's largest voting bloc, says Patrick Goldstein in the Los Angeles Times, and they're particularly "queasy about rewarding a special-effects driven film [like Avatar] that...did little to honor the actors' craft." The Academy, in general, still rejects "films largely created and sculpted in the computer," even "game-changing" blockbusters like Avatar.

2. Science fiction never wins Best Picture
Avatar is just the latest hit "doomed because it's sci-fi, a genre that has rarely been rewarded by Oscar," says Alex Ben Block in The Hollywood Reporter. Remember: Star Wars lost to Woody Allen's Annie Hall, and E.T. lost to Gandhi. Though The Hurt Locker managed to avoid Oscar's "Iraq War curse," Avatar couldn't "sidestep the science-fiction label."

3. Patriotism beat out anti-Americanism
Even though Hollywood is "overwhelmingly left-wing," it rejected the "overtly anti-American and anti-military" Avatar, says Nile Gardiner in The Daily Telegraph — uncharacteristically backing The Hurt Locker. This suggests that voters really considered it the better film. Hopefully Cameron will focus on a compelling storyline next time.

4. Hollywood is elitist and navel-gazing
Avatar would clearly have won a national popular vote, says Brian Moylan in Gawker. But "the Oscars are not about America, they are about Hollywood," and shoring up its ego. Like Sunday's Oscars telecast, Hollywood is a "complete self-referential mess."

5. The Hurt Locker is brilliant in ways Avatar is not 
"The bottom line is that it's easier to make a movie with great special effects," says Zennie Abraham in the San Francisco Chronicle, "than a timely film with a good story." The Best Picture Oscar is supposed to go to the story that makes you think about the world around you, and The Hurt Locker, "in so many ways, was that movie." Avatar was not.


Oscar uproar: The Hurt Locker mess