NOTE: SPOILERS AHEAD FOR THE MARVEL CINEMATIC UNIVERSE FILMS.

"Plot hole" is a term used to describe inconsistencies or lack of explanations in the logic of a film's plot. They have gained a negative connotation over the years, but to be frank, plot holes are almost always an unavoidable aspect of film-making. For instance, does it make logical sense that every superhero in the Marvel Cinematic Universe doesn't show up whenever there's a crisis (like when Earth was invaded in Thor: The Dark World)? Of course not, but you obviously can't have every superhero show up in every film, hence you pretty much have to have a plot hole there. It's unavoidable.

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Similarly, sometimes you just want a character to do action X, even if you don't have an explanation for why they would do action X. Is it better if you have an explanation? Of course, but sometimes it isn't feasible and sometimes it would just take too much time to explain it all (often, plot holes are created by an explanatory scene being cut from the film due to time). So we don't begrudge the Marvel Cinematic Universe its plot holes, but at the same time, it is fun to talk about them. Here are the 15 biggest MCU plot holes.

15 YOU ARE NOT ALONE (JK LOL)

The very idea of the Marvel Cinematic Universe was created by the post-credits scene at the end of Iron Man, where Nick Fury shows up and tells Iron Man that he is there to recruit him for the Avengers Initiative. In the second Iron Man film, Fury explains that they have decided not to recruit him.

Here's the problem, although Fury tells him, "What, did you think you were the only superhero around?" Tony, at the time, was the only superhero around! Hulk, Thor and Captain America did not come around until after the events of Iron Man (remember, S.H.I.E.L.D. thought Thor was just a nut when he first showed up). There really was not an Avengers Initiative back then (no offense, Black Widow and Hawkeye).

14 DON'T BRING SIX GUNS TO A SUPER-ARMOR FIGHT

In a classic reveal at the end of Iron Man, we learn that Clark Gregg's seemingly boring bureaucrat who has been bugging Tony and Pepper Potts the whole movie turns out to be Coulson, a real life Agent of S.H.I.E.L.D.! Coulson and his agents know that Obadiah Stane: has built an Iron Man-like armor and they are there to help protect Pepper.

However, if they know that Stane has built an Iron Man-like armor, why did they just show up with five agents with just regular guns? Why not use some of their high-powered S.H.I.E.L.D. weaponry? Or show up with more men? Most likely, it was a mix of budgetary concerns and a desire for Iron Man to be the one who saved the day, but in story, it did not make sense.

13 TAKE MY BREATH AWAY

In a touching scene at the end of Guardians of the Galaxy Vol. 2, Yondu and Star-Lord recreate an iconic scene from the end of the first Guardians of the Galaxy film where Peter seemingly sacrificed his life to save Gamora by giving her his oxygen. Luckily, due to being part living planet, Peter was able to survive outer space exposure until he was rescued.

After Peter lost his powers at the end of the second film, his surrogate father, Yondu, sacrificed his life by giving Peter his oxygen and spacesuit as they escaped from a collapsing Ego (the living planet). However, since the Guardians knew that Yondu had gone after Peter with just one spacesuit and since they were right there with a spaceship, why didn't they try to grab Peter and Yondu before they broke out of the atmosphere of Ego?

12 PEOPLE IN GLASS HOUSES...

In Iron Man 3, Tony Stark is distraught when a bombing attack by the mysterious terrorist known as the Mandarin (later, we learn that the Mandarin is just a front for the real bad guys, with an actor pretending to be the so-called Mandarin) injures his friend, Happy Hogan. So Tony then decides to go on national television and give out the address of his Malibu mansion and dare the Mandarin to attack him.

That's all well and good, but when the Mandarin does just that, Tony is not even remotely prepared. We guess that you could argue that Tony was just being stupid, but that still seems like an awfully strange thing to say and then have Pepper Potts and Maya Hansen in his home and not even have his Iron Man armor on!

11 LITERALLY DRAX

One of the many funny bits in the original Guardians of the Galaxy was the fact that Drax the Destroyer did not understand the concept of metaphors. As Rocket Racooon explained to Star-Lord, ""His people are completely literal. Metaphors are gonna go over his head." Drax then responded to that, "Nothing goes over my head! My reflexes are too fast. I would catch it."

It's a funny bit, but then it was constantly inconsistently applied within the rest of the film (perhaps most aggravatingly when he calls Gamora a "whore"). For instance, at the climax of the film, Star-Lord asks the other Guardians if they will all "give a shit" with him. They all agree to do so, even though a literal-minded Drax would not do so.

10 STANE'S END GAME

iron monger about to attack

Up until the end of Iron Man, everything Obadiah Stane had planned was cleverly shrouded in both secrecy and deniability. He cut a deal with the Ten Rings terrorist group to kill off Tony Stark for him so that Stane could take over Stark Industries. When that failed, they gave him what was left of Tony's original armor to make up for it, which Stane then used to create new armor.

Okay, but why does Stane then put on the armor and expose himself as a robo-terrorist? Even if he succeeded in killing Tony, his plans for the company were going to be ruined no matter what. Heck, he did not even know for sure that he would fight Tony at the end (he just knew he was attacking the SHIELD agents). So why not flee the country when he could to start over with his new armor tech?

9 MYSTERY OF THE AETHER

The powerful weapon at the heart of Thor: The Dark World was the Aether, which was really the Reality Stone. It was an extremely powerful weapon and yet was inconsistently used throughout the film. In the opening scene, set millenia ago, Malekith and the Dark Elves are waiting to use the Aether to end the universe when Bor (Odin's father) and the Asgardians attack. Had Malekith just merged with the Aether (like he does later), the Asgardians never would have been able to stop him (he couldn't activate its full powers until the worlds were in sync, but he could have accessed it first).

When Bor captures the Aether, he puts it into another dimension for safekeeping, but fully exposed so that Jane Foster could easily access it and merge with it when she ended up in that dimension. For something so dangerous, Bor didn't really seem all that concerned.

8 ZEMO'S PLAN

At the heart of the plan of Zemo in Captain America: Civil War, he just wanted Iron Man and Captain America to pay for what he believed to be their responsibility (as the heads of the Avengers) for the death of his wife and child in Sokovia after Ultron's attack there in Avengers: Age of Ultron. That part was compelling.

However, Zemo's plan to get there required so many very specific things going just the way that he planned them (like, for instance, no one knowing what the psychiatrist that was brought in to talk to the Winter Soldier looked like) that his plan ultimately looks absurd in retrospect (for instance, if someone else captures or kills Winter Soldier at any point in the plan, everything is ruined).

7 WHAT THE FRIGGA?

In Thor: The Dark World, Jane merges with the Aether, and upon doing so, she awakens Malekith from suspended animation, who now needs to track her down to get the Aether so he can complete his plan to transform the entire universe into an awful place. Jane is taken to Asgard for protection, but Malekith and his allies cut a swath of destruction in Asgard trying to get to Jane.

Frigga uses her magical powers to create an illusion of Jane to fool Malekith. However, a couple of things - Malekith was able to track Jane all the way across the universe due to her being merged with the Aether, but then he was fooled by an illusion of her? Secondly, if the illusions were that good, why did Frigga not use one for herself? Instead, she is killed by Malekith! We know the plot needed her dead, but still!

6 CAP STAKED HIS LIFE ON A BAD PLAN

Zemo's plan in Captain America: Civil War seems downright smart when you compare it to Captain America's plan at the end of Captain America: The First Avenger. Captain America's plan involves him breaking into Red Skull's stronghold by himself, fighting a bunch of Skull's Hydra troopers before getting captured, taken to a specific room and then having his comrades break through the windows of that room to save him.

However, the plan involves him knowing that he would not be killed and there's no good reason why he would think that they wouldn't just kill him, especially because the Hydra troops are trying to kill him when he first attacks! Plus, what if he was not taken to that specific room in the giant stronghold? Things happen because they need to happen, but Cap's plan is nuts.

5 INFINITY STONE TRADE

The framework of the Marvel Cinematic Universe is leading up to Thanos putting together all of the Infinity Stones to form the Infinity Gauntlet (and yes, we know that they showed an Infinity Gauntlet as an Easter Egg in Thor, but we're not counting an accidental Easter egg as a plot hole). Choosing not to directly involve himself, he has been using agents in the various films.

In Avengers, he uses Loki to get him the Tesseract, which was powered by the Space Stone. That makes sense. However, he sends Loki using a scepter that is powered by one of the Infinity Stones that he is desperately trying to collect (the Mind Stone). If the Infinity Stones are so important to him, why would he risk losing one he already had to get a new one? And sure enough, Loki does lose the Mind Stone!

4 USELESS IRON MAN ROBOTS

At the end of Iron Man 3, Tony Stark uses his artificial intelligence, Jarvis, to help remotely control all of Tony's other Iron Man armor. It was a cool scene to see all of those armor show up to help save the day, but it then opens up the rather clear question - "if you had access to a legion of remote controlled Iron Man robots, why didn't you use them earlier in the film?"

For instance, if you just told the Mandarin to attack your home, maybe have your Iron Man robots protect your home? If you're sneaking into the Mandarin compound without any armor, maybe have your Iron Man robots help you? They tried to explain by saying that they were stuck in the destroyed mansion, but clearly they weren't since they showed up in the end (and, again, why weren't they deployed before the mansion was destroyed?).

3 VANKO'S HEALING POWERS

The villain in Iron Man 2, Ivan Vanko (a mixture of two classic Iron Man villains, Whiplash and Crimson Dynamo), makes his debut attacking Iron Man at the Monaco Historic Grand Prix with his special electrified whips. Vanko does not wear a whole lot of clothes, so it makes it curious as to how he manages to do so well as a villain. For instance, no guards at the race try to shoot him. Perhaps he would have deflected the bullets with his whips, but no one even tries.

However, Vanko was then rammed into by Happy Hogan's car not once, but twice! Yet, later in the film, he is walking fine despite having a car repeatedly crush his legs! The film even makes it look like Vanko lost his legs period due to weird camera angles. But either way, he should not be walking later in the movie.

2 CAP'S CRASH

At the end of Captain America: The First Avenger, Captain America boards the Red Skull's giant plane, which is filled with smaller planes designed to launch and then drop weapons of mass destruction around the globe. For some reason, despite it not really saying it anywhere, Captain America deduces that the large craft is destined to crash into New York City and explode (how he reached this conclusion is not explained).

Cap then insists on crashing the plane into the Arctic. However, there's never an explanation for why this had to be done. The plane was set to fly over the Atlantic, it wasn't like there wasn't time to figure out another plan. Since Cap had to land in the Arctic so that he could go into suspended animation, though, that's what happened, whether it made sense or not.

1 DID HOWARD STARK HATE HIS SON?

One of the major plots in Iron Man 2 is that the palladium that Tony Stark uses in the arc reactor that he needs to stay alive is slowly poisoning him. Since he can't replace it with anything else, he is sort of screwed. Luckily, later in the film, Nick Fury gives Tony a box of some old materials owned by Howard Stark, Tony's father.

While watching a film in the box, Tony realizes that his father has left for him a clue to a new element that Howard couldn't synthesize in his time (Tony says he can't do it now, either, but then does so anyways, which is weird). That element happens to replace palladium and save Tony's life! The plot hole, of course, is that Howard couldn't possibly believe that his son would ever see his message by doing it this way, so why do it that way?

Can you name any other major plot holes from the Marvel Cinematic Universe? Let us know in the comments section!