Looper is a highly thought-provoking adventure that leaves lingering questions about its compelling time travel logic, but the movie's entire plot only takes place due to an administrative oversight by faceless characters. The Looper canon is impressively in-depth for a standalone story and makes Rian Johnson's fictional universe very immersive. While the movie's worldbuilding is rewarding, none of it would have been possible to explore if one key part of Looper lore happened a little differently.

https://screenrant.com/looper-plot-avoid-small-universe-character-change/