THG was told in rigid first person. This was Collins’ choice. We see nothing that transpires beyond the curtain of her hero’s awareness. Which limits the ability to fully understand the motives and Machiavellian cruelty of the folks who are pulling the strings of the Games themselves.
The more we understand that, the more emotion we’re likely to invest. This is what the filmmakers knew, and why they changed the story.
In the book we only get a historical overview from Katniss’s POV. We never meet President Snow or the head Gamekeeper. We never see the machinations of folks with crazy facial hair pulling levers that result in fires and parachute deliveries and digital hounds from hell ....I enjoyed The Hunger Games novel (you can check out my review here), but the above argument fits perfectly with what I’ve written on first-person point-of-view. It is an incredibly limiting viewpoint, and it necessarily eliminates all those great scenes from the bad guy’s perspective. Again, try to imagine Stephen King’s The Stand without all those scenes involving Randall Flagg. It would be an inferior novel. (Incidentally, you can read Mr. King's review of The Hunger Games here.)
Now, whether The Hunger Games would have been better if it had been written in third-person limited – which would have revealed some story events from the bad guy’s POV – is a matter of opinion. But it illustrates perfectly the significant considerations an author must weigh in deciding upon the best narrative viewpoint for his or her story. If you have an opinion on the narrative viewpoint used in The Hunger Games, post a comment and let me know.