Box Office Bomb: One of the biggest in recent memory. It cost an absurd $250 million to make and pulled in an anemic $73 million at the domestic box office. Overseas was much much better at $211 million.
If this math seems funny to you first consider marketing is good for at least another $100 million. Secondly the studio does not receive all of that box office money, it splits about half with theater chains domestically. Overseas returns are even lower, where some nations like China don't allow more then 25% of a film gross to leave the country. Also major individuals like directors often have a cut of the gross.
Disney predicted a $200 million dollar loss on the film and this could be optimistic or counting on DVD/Blu-ray sales. Without the actual books its impossible to be sure.
Creator Killer: Studio executive Rich Ross was fired from his position as Disney Studios leader weeks after Disney predicted they'd lose $200 million on the project. Also resulted in a Stillborn Franchise for the foreseeable future.
Director Andrew Stanton has possibly survived being slated to direct Finding Dory due in 2016. Its unlikely he will be allowed to work in live action again.
The two really weren't competing against each other as the films were aimed towards totally different audiences (this film for young males, The Hunger Games for teen girls). This film's actual rival was Wrath Of The Titans (a similar literary concept with big action sequences, a buff male lead and releases in 3-D).
Executive Meddling: The film was apparently titled John Carter of Mars at first. A promotional logo for the film is a stylized "JCM". But then Mars was dropped, leaving the film with a nondescript title. John Carter is a quite ordinary name compared to the likes of Flash Gordon or Buck Rogers and it stands out precisely because of the association with Mars. No wonder this didn't go over well with fans and others. Not to mention that Mars, including the JCM logo, was downplayed in the marketing (along with any mention of creator Edgar Rice Burroughs, the guy also responsible for Tarzan among others...)
Ink Stain Adaptation: Don't expect anyone else to touch this franchise again for at least a few decades.
Old Shame: Andrew Stanton has already confessed that he isn't too satisfied with how the movie turned out.
Troubled Production: There were reservations at Disney about letting Stanton direct the film, despite his obvious sentimental attachment to the material, because he'd never directed a live-action feature before. But, since he'd made WALL•E and Finding Nemo into hits, they let him do it even though he warned them, "I'm not gonna get it right the first time, I'll tell you that right now." Indeed, the film required extensive double reshoots. Throughout production, he ignored the advice of the crewmembers who were live-action veterans in favor of his Pixar friends, back in their offices. Rich Ross and the other studio executives at Disney likewise had little experience with feature films, since most had come from television.
Then, it came time to market the film, which was already handicapped in that department by having no big stars in the cast. A trailer shown at a Disney con did not go over well, and Stanton refused to take any advice from the studio's marketing department. He insisted on using Led Zeppelin's "Kashmir" in the trailer even after it was pointed out to him that a 30-year-old classic-rock song was not likely to resonate with the younger male audience the film was intended for. In addition to all the titling problems noted above.
Granted, once one remembers that film journalists get much of their information from executives, perhaps the above should be taken with a massive grain of salt as an attempt to throw Stanton under the bus.
The film's budget qualifies all on its own. At $250 million dollar budget is some $20 million more then James Cameroon spent on Avatar. And unlike the man behind then highest grossing film in history, Director Stanton had never made a live action picture.