Cracks in Marvel's armor are beginning to show after a decade of unprecedented success

• Recent MCU movies have received the worst CinemaScore grades and critic reviews of the franchise.
• They can, for the most part, still be perceived as box-office successes.

After a decade of unprecedented success, the Marvel Cinematic Universe has been hitting some speed bumps.

They aren't enough to knock off course the biggest movie franchise ever, which has grossed over $25 billion globally across 29 movies in 14 years. And Disney-owned Marvel Studios' presentation at San Diego Comic-Con over the weekend provided plenty of optimism for its future.

But it's been hard to ignore the cracks appearing in Marvel's armor. The last few movies, aside from "Spider-Man: No Way Home," have been met with muted audience response.

• "Eternals" received a B grade from CinemaScore, a company that surveys audiences in theaters on a movie's opening night. It's the lowest grade in the franchise's history.
• "Eternals" made $402 million worldwide, a disappointing figure for most big-budget movies today and especially for an MCU movie (granted, theatrical attendance was still sluggish in November, 2021).
• This year's two releases, "Doctor Strange in the Multiverse of Madness" and "Thor: Love and Thunder," both received B+ grades, the second-worst scores. Every other MCU movie has gotten an A- or higher.

"Doctor Strange" and "Love and Thunder" fared better at the box office. The former made over $900 million, the latter has grossed $600 million worldwide in two weeks, without China, which puts it on a similar track as its predecessor, "Thor: Ragnarok."

So CinemaScore grades don't tell the full story, and as long as Marvel movies keep making money, it's impossible to count the franchise out.

But it does hint at some level of audience exasperation that the MCU really hasn't had to cope with since launching in 2008. Fatigue has a chance to set in as the franchise churns out more content — it has at least a dozen movies and TV shows coming out in the next three years.

However, quality could be just as much, if not more, of a factor as quantity.

Critics say the MCU has lacked direction since 'Avengers: Endgame'

I'm far from the first to point out the MCU's current state. Those movies have also received some of the worst critic reviews of the franchise. Some have griped that the MCU has felt directionless after 2019's "Avengers: Endgame," which concluded over a decade's worth of storytelling.

In his review of "Love and Thunder," Indiewire's David Ehrlich wrote that the movie confronted the "aimlessness" of the post-"Endgame" MCU.

A recent episode of The Ringer's "Big Picture" podcast was titled "Five Ways to Fix the Marvel Crisis." Entertainment journalist Matt Belloni asked "Does Marvel have a quality problem?" on his own podcast, "The Town."

And then there are the Disney+ TV shows. Disney doesn't release viewership figures for them, so it's harder to gauge their success. But third-party data offers a glimpse.

Recent data from Parrot Analytics, which measures audience demand, showed that each of the series had a similar growth trajectory and then similar declines in engagement. It suggested that the Marvel shows have been hits with Disney+'s existing subscribers (and the Marvel fanbase), helping to retain users, but haven't gone far in attracting new fans and growing the subscriber base.

Watching the MCU could be like reading comics

If Marvel Studios had been paying attention to any criticisms against the MCU, it defiantly came out swinging at its Comic-Con panel on Saturday.

Marvel Studios president Kevin Feige announced a relaunch of the fan-favorite "Daredevil" TV series to Disney+; release dates for "Blade," "Guardians of the Galaxy Vol. 3," and more; and two new "Avengers" movies, both set to be released in 2025, that will conclude the post-"Endgame" "Multiverse Saga."

The first trailer for "Black Panther: Wakanda Forever" was viewed 172 million times in its first 24 hours, according to Variety. So, Marvel still has a lot of power over audiences.

But as an avid comic reader, I can't help but feel the MCU is getting closer and closer to being a true comics universe on the screen. Yes, that's what it has always been, but up until last year, there were a couple movies a year that culminated in an event film.

Now, there are a few movies and a few TV shows a year, and it might be like that for the foreseeable future. Some might be essential in understanding the grander ambitions of the franchise, like "Loki" and "Doctor Strange in the Multiverse of Madness." Some might not factor into it all that much, if at all, like "Love and Thunder" and "Moon Knight."

As Graeme McMillan wrote for Wired, "It's time for fans to watch superheroes like they read them."

As the franchise grows, audiences might find themselves being more selective in what they consume, and gravitating towards their favorite characters or the buzziest titles — just like reading comics.