The post-apocalyptic The Hunger Games franchise explains the dangerous games as a propaganda tool for The Capitol, but what if Panem is using the games to secretly rank each district's warriors? The games themselves took up most of the runtime for both The Hunger Games and Catching Fire while Mocking Jay - Part 1 and Mockingjay - Part 2 chronicle what happens after the Quarter Quell and the fall of The Capitol. The series is an adaptation of the young adult novel trilogy of the same name, penned by Suzanne Collins. While some events do change from what's chronicled in the books, the characters and the games themselves are a nearly perfect representation.
Information about the history behind the Hunger Games comes mainly from the book series. After the fall of North America, a new totalitarian government and nation formed called Panem. The land and people are separated into districts and are forced to provide economic and material services to The Capitol. District 13 rebels against The Capitol, leading to a civil war. Unfortunately, District 13 agrees to a ceasefire and is allowed to operate outside of Panem, but only if they keep the district looking desolated and maintain a non-aggression pact. The post-civil war period is known only as the "Dark Days." The remaining Districts are quieted by the Treaty of Treason, and the invention of The Hunger Games as a reminder of the past insurrection. However, what if there's a different reason behind the games?
One theory proposed on Reddit is that the Hunger Games are actually a tool secretly used by The Capitol to rank warriors from each district. After the First Rebellion of District 13, President Snow's main job as a dictator is to keep his people from an uprising. The Hunger Games are a perfect cover for this, as casualties don't really matter to the government and the warriors are in an extremely controlled environment. It's possible that Snow rounds up a small sample from each District during The Reaping to keep a close eye on his people while trying to assess any threats there may be. For example, if someone performs well in the Games then that probably means they're receiving some type of combat training. Hunger Games' Districts 1 and 2 tend to have the best warriors because they're well-treated by the government, but that may be because Snow realizes that those Districts would be the biggest threat in an insurgence as they're the closest geographically, as well as the wealthiest. So, he keeps them happy. By handpicking the Hunger Games champions and putting them in a controlled environment, President Snow is able to see which Districts fight well, how big of a threat they are, and what countermeasures to put in place.
There are a few things that this theory runs up against, however, largely the implication of how the games are planned out and the random sampling aspect. In Catching Fire, Plutarch mentions to Katniss that the arenas are built years ahead of time, while the more nuanced elements are plotted out by the Gamemakers several months in advance. So while the environment is controlled it's not really catered to show anything in particular. Second, the chances of finding out any information from such a small sample size are implausible. Those desperate for food can enter their names multiple times in The Reaping for certain benefits, highlighting that the starving are likely to join a rebel militia. However, it seems more like the extra entries are just another way for The Capitol to exploit its people, rather than to test out any theories about another rebellion.
This Hunger Games theory does have a lot of potential. Any dictator would happily put their people through something as grueling as the Hunger Games in order to test for likely insurgence and countermeasures. However, there are a few elements that don't line up with the theory. Ultimately it may be true to an extent, but not even President Snow could determine a District's ability to fight back based on a two-person sample size.