The original Hunger Games adaptations are a bit of a miracle in that they basically stopped after the story was told. While modern franchises embrace open universes and wildly expanding plots, it remained focused on a single character -- Katniss Everdeen -- and more or less walked away once she reached her happy ending at the conclusion of The Hunger Games: Mockingjay, Part 2. Considering the box office returns, it takes a lot for a studio to accept that a given cash cow has run its race. While The Hunger Games isn't the only franchise with such discipline as the Twilight franchise similarly walked away from a big moneymaker, it's unusual enough to merit mention.
Source：https://www.cbr.com/the-hunger-games-songbirds-snakes-prequel-works/
