Imagine there was a film series that did some truly great things for the superhero genre over the years, providing films that are not only quality entertainment, but also helped define and redefine what a comic book movie can be. Now imagine that fans chose to define this series not by its many triumphs, but instead by its few shortcomings. Seems odd and more than a little unfair, doesn't it? Well, that's exactly what tends to happen when people discuss 20th Century Fox's X-Men film universe.

Make no mistake, the X-Men series does have some awful entries, namely X-Men: The Last Stand and X-Men Origins: Wolverine. However, it also has entries that are pretty good, such as the original X-Men film, X-Men: First Class, Deadpool 2 and even unfairly maligned entries like The Wolverine and X-Men: Apocalypse. And then, of course, there's the truly great films the series has to offer, like Deadpool, X2X-Men: Days of Future Past and the certifiable masterpiece that is Logan.

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Point being, there is a lot more good in this series than there is bad. Yet, for some reason, as opposed to other popular superhero franchises in which the bad films are considered to be isolated outliers, fans of comic book films tend to treat the X-Men series like its films are bad by default, which is simply not the case.

To illustrate this point, let's look at three trilogies that helped define the modern superhero film: the Blade trilogy, Sam Raimi's Spider-Man trilogy and the original X-Men trilogy. In addition to ushering the superhero genre into a new era around the turn of the century, something these series also have in common is the quality of their films. In each case, the first film in the trilogy was good, the second was great and the third was awful.

However, when people discuss the Blade series, they tend to sweep Blade: Trinity under the rug, dismissing it as a film that shouldn't detract from how important its predecessors were to Marvel's cinematic history. When discussing Raimi's Spider-Man films, people also tend to overlook and, in fact, sometimes even defend Spider-Man 3, in spite of its many faults. At any rate, they still like to focus on how good the first two films were, rather than focus on the third film's problems. Rightly so.

Yet, when the X-Men trilogy comes up, fans tend to focus on the hot mess that was The Last Stand, acting as if its mistakes completely invalidated its predecessors, despite X-Men being very good and X2 arguably being the single best pre-MCU Marvel film, perhaps second only to Spider-Man 2. This can be seen as the beginning of a harsh double standard regarding Fox's mutant universe that lingers to this day.

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Granted, following The Last Stand, it did take Fox some time to regain their footing regarding the X-series. After all, the next film we got was X-Men Origins: Wolverine, which does deserve every bit of criticism it gets on account of it being a nonsensical disaster. Even then, though, with one good movie (X-Men), one great movie (X2), one bad movie (The Last Stand) and one awful movie (Origins), the series had effectively broken even in terms of quality. From that point on, the franchise has largely only soared.

For starters, 2011's X-Men: First Class was a comeback story if ever there was one. It wasn't quite a masterpiece, but it was still an exceptionally fun superhero film that also made for a rather terrific period piece that expertly blended humanity's feelings towards the mutants with the Cold War paranoia of the 1960s. From there, we got arguably the best mainline X-Men film in 2014's Days of Future Past, which featured a compelling story with brilliant set pieces, made for yet another exceptional period piece and even erased the mistakes of The Last Stand from the series' continuity.

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It was around this point that the franchise also achieved massive success by going beyond its comfort zone and experimenting with genre filmmaking. 2016's Deadpool was not only a big hit both critically and commercially, but also became a trailblazer in the world of superhero films for its raunchy, R-rated comedic tone. Then, one year later, Fox practically perfected the R-rated superhero film with Logan, a graphically violent, yet deeply emotional modern western. And that's not even taking into account The New Mutants, the X-series' upcoming venture into the world of horror.

But, rather than all of these success stories, what do fans choose focus on? Well, films like The Wolverine and X-Men: Apocalypse. What makes this especially baffling is that neither of those films are even that bad, all things considered. They're not nearly as good as the other post-2010 X-Men films, mind you, but are still perfectly enjoyable in their own right. Yet, they're still pointed to as "proof" that Fox's series is no good, despite the actual numbers suggesting otherwise.

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When Marvel Studios makes the occasional lackluster film, such as Iron Man 2 or Thor: The Dark World, fans are quick to forgive the slip up because the franchise, by and large, is still an incredibly good one. But, even though Fox's X-Men universe is very similar in terms of the larger good-to-bad movie ratio, for some strange reason the good movies are still treated as the exception, not the rule.

Sure, when the franchise puts out especially great or simply very popular films, such as Deadpool, Logan or Days of Future Past, there is an occasional burst of overwhelmingly positive feedback. Once the initial hype dies down, though, the status quo of throwing blind hate at the X-Men series typically starts up again in short order.

This stigma is so bad that some Marvel fans are already completely dismissing Dark Phoenix, despite the film still being months away from release. At this rate, it could be a five-star masterwork, but it still wouldn't matter to so many because they already have their minds made up and are simply waiting for Marvel Studios to take the reigns. The discourse surrounding the upcoming film does help shed some light on why exactly the X-Men series is as unfairly hated as it is.

Often times, people don't like to look at what is, but at what could be. As the adage goes, the grass is always greener on the other side. As such, it seems that fans are so preoccupied with wondering what the MCU could do with the X-Men that anything made by Fox is automatically deemed inferior. Therefore, not deserving of praise, even when it's more than warranted.

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Another possible explanation is that the awful taste left in some people's mouths by films like The Last Stand and X-Men Origins was simply too much to justify coming back for more, which is fair, but still incredibly unfortunate in the grand scheme of things. Especially considering all the great things the franchise has done since then, both on the big screen and through exceptional television shows like Legion and The Gifted.

Fox's X-Men franchise has had its missteps, there's absolutely no denying that. But what superhero franchise hasn't? Ultimately, the fact of the matter is that the X-Men universe has provided some of the most important superhero films of the last two decades. And with the Disney/Fox merger on the verge of being finalized, it's a franchise that could very well be ending soon, at least in its current form.

Marvel Studios will no doubt be able to do some great things with the mutants, but one can only hope that, as time goes on, fans will remember Fox's X-Men series for its impeccable influence and not simply as the "other" Marvel franchise that "wasn't as good as Disney's."