10 Movie Endings That Basically Doomed Their Franchise
5. "Fixing" The Timeline - X-Men: Days Of Future Past
The Ending
The film concludes with Charles Xavier (James McAvoy) convincing Mystique (Jennifer Lawrence) to spare the life of Bolivar Trask (Peter Dinklage), ensuring that the Sentinels are never created and the original apocalyptic timeline in 2023, where most of the X-Men are killed, never comes to pass.
Wolverine then wakes up back in 2023 at the X-Mansion, where all the mutants' lives have been saved.
Why It Doomed The Franchise
Though there's an argument to be made that Days of Future Past is one of the best X-Men movies and ties off everything with a neat bow while erasing some of the more problematic films from the timeline, that's only really true if it had been the final entry into the series.
Instead, Days of Future Past as a whole and especially its ending introduced several nagging problems.
First of all, the film's general time-hopping shenanigans snapped the series' already loose grasp on continuity in half, with both X-Men: Apocalypse and X-Men: Dark Phoenix leaping forward around a decade each into the future, despite the cast members clearly not ageing to reflect that time jump.
Days of Future Past also created the fixed end-point of 2023 where the timeline was repaired, an ending which the subsequent sequels didn't seem remotely interested in working towards, especially Dark Phoenix.
Now, there are definitely external factors that harmed the series here, namely Sophie Turner's questionable casting as Jean Grey and the Disney/Fox merger, but as good a movie as Days of Future Past is, it's also where the wheels began to come off the franchise.
This is exemplified by no subsequent mainline X-Men movie turning out much good, and the only quality offerings being spin-offs such as Deadpool and Logan.
You can certainly appreciate why Bryan Singer and Simon Kinberg wanted to make the movie, but the irony of it "fixing" the continuity is that it also created major problems for the rest of the series' tenure.