Infinity War is the culmination of 10 years and 18 films of storytelling, something that Hollywood has never attempted. While the original Avengers film performed the rare feat of satisfying fans' expectations while bringing together its roster of heroes in a single film, the scale of Infinity War (which features over 20 different heroes from across the MCU) makes Joss Whedon's 2012 movie look small in comparison. Perhaps unfairly, it's hard for audiences to allow projects on this level to just be films.

Of course, Infinity War is not the first film to have fans lining up in anticipation months before it's seen, circulating rumors and theories of what will transpire as the clock ticks ever closer to release. Rarified films such as these generally fall into three categories upon release.

1. The Gold Star Kids (See: 2012's The Avengers). Movies that people obsess over for years before the release, and that deliver in every way people want.

2. The Above Average Students Who Deserve More Credit (See: Avengers: Age of Ultron). These are movies that may be a solid B instead of the A+ people expected, so they are ripped apart. Perhaps it's because fans had already written a movie in their heads and were disappointed when that didn't pan out.

3. The Underachievers (See: 2016's Batman v Superman: Dawn of Justice). These movies enjoy an incredible buildup, but just fail to deliver.

One of the first examples of such fan fervor is 1999's Star Wars: Episode I — The Phantom Menace. Given the time period the film was released in, during the dawn of the Internet Age, it was perhaps the first to get the web energized with conspiracies, arguments and eager suspense over what George Lucas had planned for his first trip back to a galaxy far, far away in nearly two decades.

So eager for any bit of footage from the upcoming movie were fans that a bootleg version of the first trailer (recorded in a theater and leaked online in the days before YouTube) became so widely circulated that Lucasfilm was forced to upload an official version of the trailer the next day.

As time has marched forward, the current culture of instant information that blossomed with the pervasive spread of social media has further fueled speculative discussions of upcoming movies. Fans and media outlets alike clamored for any bit of new footage they could get their eyes on when Christopher Nolan's The Dark Knight was ramping up for its theatrical run in summer 2008.

While that film was a massive hit that largely lived up to, if not exceeded, expectations, its 2012 follow-up, The Dark Knight Rises, similarly fueled massive speculation, but failed to resonate with fans in the same way. Nolan is not the only director to have a sequel fail to live up to a predecessor.

Whether in spite of or because of the popularity of the franchise, anticipation was sky-high for both Bruce Wayne's return in The Dark Knight Rises and the Avengers' second team-up in Whedon's Avengers: Age of Ultron in 2015. Like Nolan three years before, Whedon had to deal with unreasonable high expectations for his sequel, and fans were disappointed. Both films were successes financially, of course, but their place in the zeitgeist is significantly less than their predecessors.

More recent examples of the double-edged sword that is feverous anticipation are The Force Awakens and The Last Jedi. Fans were beside themselves with excitement over a return to the Star Wars universe when J.J. Abrams' 2015 film was first announced. That intensity lasted all the way through the film's promotional run (helped in large part by the cryptic rollout of basic plot details from the studio and Abrams himself) and cemented The Force Awakens as the No. 1 domestic grossing film of all time. People were so happy to have a Star Wars movie that felt like the films they grew up on that there was little grumbling at the time of the film's release (though later people would complain that it echoes A New Hope too closely).

Conversely, when director Rian Johnson's The Last Jedi was released last year, fans were so upset by the film's content that a change.org petition was started to have the movie officially removed from the Star Wars canon, with more than 100,000 people signing it. The film was a hit, grossing more than a billion dollars worldwide, but significantly underperformed when compared to The Force Awakens, which earned almost a billion dollars more globally.

While Abrams' film widely connected with audiences and lived up to the mammoth hype (it has a 93 percent rating on Rotten Tomatoes with an 88 percent fan rating), Johnson's decision to eschew many fan theories circulating online before the film's release caused a major backlash (The Last Jedi has a 91 percent Rotten Tomatoes score, but only a 43 percent fan rating). Personal opinions and subjectivity aside, the film is evidence of how failure to meet lofty expectations can often be unfair to filmmakers.

Avengers: Infinity War is destined to make untold piles of money, and given the track record of Marvel Studios and filmmakers Joe and Anthony Russo, it's just as likely to be a hit with critics. But when it comes to fan response, here's hoping it manages to find that sweet spot between unrealistic expectations and reality.