Not all stories need continuations, but when something we’re fans of does, we expect some level of respect for the source material. After all, if we loved something, it’s because of the care and attention the creators gave that product; we only ask that the same care is maintained from movie to movie.
Well, filmmaking is a business, and when something sells, you need to make more. Having no ideas or time to do the next thing is no excuse, apparently, since the machine needs to keep churning content. This is how we end up with sequels that don’t value us as consumers at all.

Highlander II: The Quickening
The sequel completely rewrote the mythology of the original movie by turning immortals into aliens, instantly alienating fans who loved the fantasy-mysticism approach of the first film.

Star Wars: Episode VIII – The Last Jedi
Rian Johnson deliberately challenged audience expectations surrounding Luke Skywalker and franchise mythology, creating one of the most divisive fan reactions in blockbuster history.