When Marvel comes to mind it's always either the Avengers together or individual super heroes part of the Avengers. Nobody really thinks about X-men in relation to Marvel. They're almost as out there as The Fantastic Four. Great comics, but awful on screen execution.
There are many reasons behind why the X-Men aren't really part of the Marvel Universe. For starters, you already have the Avengers, what more can you need? The world is already being taken care of in the hands of superheroes, nobody needs another group of heroes.
Secondly, unlike other Marvel related on screen movies, X-Men doesn't really have the most consistent cast. Look at Iron Man for example, throughout the films it's been RDJ, or look at Thor, throughout the films it's predominantly Chris Hemsworth. Unlike other movies, there is not much of a flow behind the X-Men mix up of a series. For example, X-Men universe created a whole new timeline. They went from current times to the 50's-60's to the 80's to WWI-II times and the list goes on. It's crazy, there is absolutely no executional styles between the movies.
I do have to hand it to Marvel, they were really able to pull some strings with the cast. Hugh Jackman? Classic amazing actor, same with Nicholas Hoult and Michael Fassbender. But honesty, all that money that's being spent in a show stopping cast is going to waste if there is no execution behind it. Consistently, X-Men is known to copy the play out of the Avengers series, but it really does not work for them. For example, they've tried individual films such as Wolverine, but like I said before, another flop. Marvel and X Men were never really meant to be together and that's why Marvel doesn't own rights to X Men or they own partial rights but not all.
For all of those Marvel fans out there, this one is for you. So you know how all of the classic superheroes are actually classified in main stream Marvel movies, right? Well the biggest offset between X-Men and Marvel is that X-Men throws around the term "mutant". Now, there's absolutely nothing wrong with that, but it's used in a very derogatory manner that normal Marvel movies would refuse to follow.
So to spend this rant on all things X Men and Marvel, the Marvel Universe is already big enough with the Avengers and other individual characters. X-Men should consider creating a tv show rather than a movie series, because when it comes down to things: X-Men can be one great movie and just really shitty sequels. As said above, the flow is what makes movies great. For X-Men , the non existing flow is pulling down not only their ratings but also the X-Men series.
