Stupidity: When seeing that the bridge is out, JLC could've easily climbed out of the sunroof and hop off the back of the limo and onto the pavement, suffering a few cuts and bruises at the most. I know that it would've been anticlimactic, but still.
Suggested correction: You're assuming that jumping off a runaway car is a simple task that anyone can do. She's scared out of her mind, and many people in a similar situation would probably be scared at the prospect of jumping off a moving car, even with the knowledge that they will be flying off the road shortly.
Stupidity: The X-Men depart for space on a vehicle not designed for space, for an incredibly dangerous mission they know nothing about (and none of them can survive in space at that point), but don't suit up for it in the slightest - and with Nightcrawler and Quicksilver's powers as they are shown later, it'd be easy to do it without wasting time. Not only that, but Xavier communicates with NASA to get the briefing only after the X-Men have already departed.
Stupidity: Luca's parents try to find him by splashing him with water. If they succeeded, Luca's cover would have been blown.
Stupidity: During the battle on the harvester, Chani is firing an anti-aircraft projectile at a Sardaukar approaching her. Although the projectile is strong enough to destroy an ornithopter, instead of blasting the Sardaukar away, it pushes it into the air until it hits the harvester track. (00:36:39)
Stupidity: This film portrays Michael Jordan and his family living in a relatively modest house in the suburbs. Jordan was one of the most famous people on the entire planet around the time the film takes place. Living in such an area would lead to a never-ending onslaught of overzealous fans, paparazzi, and even detractors.
Stupidity: Carol enters the Imperial Cruiser that doubles as a secret laboratory, uncloaking it. She does not cloak it back, so the villains just find it immediately. But blood-thirsty Ronan, despite having multiple ships, does not target it or acknowledge it, despite fully knowing that Earth has no defenses and is not a threat, while a Kree vessel would necessitate countermeasures.
Suggested correction: The Kree wanted what was on the ship. Destroying it would not achieve their goals. Additionally, since Carol was able to decloak it using her suit, so could any other Kree soldiers.
If to decloak it they need to know the location, it had to be visible to begin with? Going by the movie, Ronan has not even been informed about Mar-Vell's project. If the movie still remembers there is any (no indication is given), he suddenly finds a ship not part of his fleet and does not question it, simply going by what the plot wants him to do. Which, actually, could be fully intentional, since he obviously just cares about blowing stuff up and does not care even if any of his fellow Krees is still on the planet (not that the movie implies it, as movies normally would, but he's such a one-note character that it could be possible).
Earth doesn't have defenses and is not a threat, the Kree cruiser is obviously not part of Earth's defenses but is one of their own. He just didn't realise it is a target instead. Besides, Kree are on board, why would he target it?
That's exactly the point of what I originally said: Earth is not a threat, but he, fresh off his jump, right away gets in bombing mode without checking where the other Krees are (Yon-Rogg is on Earth at that exact moment, right the spot he is dropping the bombs at, even!) or batting an eye at the cruiser that happens to be already there, not target it but ask "what is going on here?", hail them or receive a report about the situation and where he is supposed to blow his load (would have been a single line of dialogue, here it seems an issue entirely ignored because plot moves from A to B): as a member of the military he is supposed to coordinate his attacks (like he did earlier on the first meeting with the Skrulls, where he bombed a specific part of the planet). Here all his instructions have been "Come at once, Earth has been infiltrated!", but he launches the bombs right away, seconds after jumping close to Earth.
Stupidity: At the start of the tanker chase Sanchez shoots at Bond. He manages to get in the cab and throw the driver out, who lands on Sanchez's car. Sanchez then gets in front of Bond and has the ideal opportunity to just shoot the cab up with his machine gun knowing Bond is driving, but he doesn't.
Stupidity: Harrigan leaves his partner's badge on his grave where anyone could take it and use it to impersonate a cop or abuse it in other ways. (00:50:15)
Stupidity: Immediately after Unkar Plutt makes Rey a generous offer for BB-8 and she refuses, he tells someone over his communicator to follow her and bring back the droid. He should have at least waited until she was out of earshot before he said that, especially if he was trying to be covert about it.
Suggested correction: But he was out of earshot of her.
I posted this immediately after watching the scene in question, and it looked as though Plutt spoke into his communicator right after Rey turned around and went on her way; certainly too soon for her to have gotten more than a few steps away. Also, he spoke at a normal, conversational volume rather than anything that sounded like a whisper or "sotto voce", so unless he was relying on the ambient noise of other nearby activity, I still believe this "stupidity" is valid.
That depends on how sneaky you think Plutt is. Rey walks away in quick paces, so she is out of earshot. Also I don't think it bothers him that much if she heard, she is just a scavenger, what can she do about it?
Rey was definitely out of earshot. Rey walks completely out of the shot, which appears to be about 10 feet away. Unkar Plutt then angrily swipes the portions off the counter and picks up his communicator. At the pace Rey was walking she would have been a considerable distance away from him when he spoke. In addition, Unkar Plutt lowered his voice when he spoke because he was being sneaky. She might have been able to hear him speak, but it is totally reasonable that she wouldn't be close enough to make out exactly what he was saying.
Stupidity: Why would Stanley say the shoes fell out of the sky? It happened under a bridge. Any normal person would instantly realise someone threw them off the bridge.
Suggested correction: It's an idiom/expression. When something turns up out of nowhere, we say "it came/fell from the sky." In fact, Mr. Sir says this to Stanley when he finds Stanley with his empty bag of sunflower seeds, "Where did this come from? Did it fall from the sky?" Obviously a sarcastic way of saying, "it didn't get there by itself, someone put it there." So the shoes obviously fell from the bridge and Stanley knows this because Zero refers to the bridge later in the movie.
Stupidity: When the policeman comes for the girls, the people run along a straight path, completely straight, without bothering to go over the fence right next to them or run in a different direction.
Stupidity: Jimmy and his friends aren't allowed by their parents to go to the opening of Retroland because it is a school night. What kind of amusement has its grand opening on a school night? It would make more sense commercially to open on a Friday or Saturday night.
Stupidity: The Good Boys were going to ride their bikes four miles to the mall but did not even think to bring bike locks with them. Also, even if there were no locks on the bikes when parked in front of the store, this does not necessarily mean that the bikes would not still be there later for the Good Boys to pick up. Thor just assumed that the bikes were lost/stolen forever because he said his family would not be able to have "Cycle Sundays."
Stupidity: During the gun battles with the "Tropic Thunder" actors, not one of the Flaming Dragon soldiers notice there is something strange about how the actors are firing their weapons (i.e, in the air, over the heads of the Flaming Dragons, etc.) or that there is no damage inflicted when the actors are shooting at or near objects in the area. Those two factors alone would tip off the Flaming Dragons that blanks were being used in the weapons of the actors.
Stupidity: Right before the movie's final battle, Sub-Zero taunts Cole with his wife's necklace and makes him chase him into a portal. Sonya was right next to Cole, and she did not come along with him. They had previously planned to take on Sub-Zero together, but apparently she just left him to chase Sub-Zero alone to an unknown location.