Movies are fuelled by conflict. The hero needs something to fight against so that they can grow and, more often then not, that conflict is incited by and represented through a central villain. In modern blockbuster filmmaking especially, a villain is a necessity to the story. A film can survive on strong acting, action and supporting characters, but the lack of a worthy antagonist often makes it a lot harder to manage a meaningful conflict.
With so many sequels and adaptations, many of these characters come into the picture with built-in expectations. Theyre meant to push the hero further than theyve been before and produce an even bigger conflict, all the while trying to live up to either their predecessor or their source material. This creates issues for character development before the movie even begins.
Beyond that, other common problems plaguing these forgettable villains are usually poor characterization and underutilization. Often, their motivations are either unclear or nonsensical, and their villainous behaviour doesn't seem like the most believable course of action for their character. A weak villain can be produced in a multitude of forms, though in these instances, at least these villains managed to successfully move the plot forward.
A good villain wont necessarily save a movie, just as a bad one wont necessarily destroy one. As such, these are the worst villains, who were over-hyped and under-delivered, that still starred in films that were strong in the end.