I am pretty sure that X-men is more than just a comic to many of us, some of use grew reading their comics and watching them on TV, seeing them face grief, win, lose, but ultimately rise up and face the challenge to protect the world that hates them and fears 'em. So I ask, what aspect of the franchise do you enjoy more, or brings you back every time to the X-books, X-men cartoons, or this very forum.
1. The characters and their interactions: What's a franchise without strong and lasting characters that build relationships over the years? With more than 50 years X-men has a wide character cast with interwoven relationships forged through fire and sweat, are those character and their relationships bringing you back every time?
2. Specific character: Every franchise has great character, some would say they're as big as the franchise itself, perhaps you love storm as the most powerful X woman, Jean as the Phoenix of death and rebirth, wolverine as the best there is, or Cyclops the prime leader and first X-man, or I could keep going... It means there's one specific character that you love and always brings you back.
3. Superheroics: What's a huge franchise like X-men without epic voyages, great battles, non stop action and over the top fights against almighty foes? Do you perhaps enjoy the X-men as superheroes first and foremost?
4. Minority / LGBT+ / Outcast metaphor: Self explanatory, X-men when written correctly works as a analogue (although imperfect) for disenfranchised races of our real society, maybe LGBT+ folks that come from different communities/societies and finds a place that welcomes them as they are, or just a kid that felt alone in his school and the X-men made him feel that there's always a place for you.
5. The Community/Fans: Large part of enjoying a hobby is interacting with the people that share it. Even if our fandom has certain reputation for being particularly passionate about our comics and beloved characters, we keep coming back every time to meet with new fans, chat with the ones we've known for a while, and remember those that are gone for several reasons.
6. X-Women: For a franchise named X-men, it features some of the better developed superheroines. One could argue they're the heart of the X-men and their presence can turn a bland book into a great one, their power turn a losing battle into an absolute victory, and their beauty illuminate every page they're in.
7. Team magneto: I've always considered the possibility that despite being a franchise that has it's roots in ideas of acceptance, it has developed the duality of Xavier v Magneto, and because of that some might want to see mutants triumph over humanity altogether, not by slaughter, but by imposing dominion over a race that hates them and fears them.