
Stupidity: After Julie tells Louis that Peyton is still alive, she notices the Bellisarius memorandum on his desk and realises he was involved with the destruction of the lab. If Louis had kept the memorandum in his desk instead of in plain sight, he would never have been found out.

Stupidity: McCord gives Lincoln and Jordan a credit card and tells them that he will have to report it missing within twenty four hours, and he warns them that they can be traced by using it. He then gives them a huge wedge of cash. Since we have a society that still uses cash, and he has acknowledged how dangerous the use of a "stolen" credit card is - he even tells them how using it will lead the authorities straight to them - why not just tell them to use the cash? (If there wasn't enough, they get a cash advance on the credit card up to its limit - easy). He repeatedly acknowledges the risks of using the card, and it is absurd to speculate that he didn't have time to find and use an ATM to max out the card. He doesn't have to find an ATM - Lincoln and Jordan do, and as he acknowledges they have twenty four hours to do so. Once the cash is withdrawn, the card is thrown away, and nobody is at risk.

Stupidity: How on earth did those helicopter gunship pilots survive a tour of duty in Vietnam? They are too stupid to tie their own shoelaces. They have encountered a thirty metre tall ape which is intent on killing the lot of them by grabbing their helicopters and smashing them to the ground, so they have two clear choices - a) use their heavy, mounted machine guns or the grenade launchers fitted to the assault rifles carried by the troops on board to shoot the thirty metre tall ape to ribbons from a couple of hundred metres away, well out of its reach or b) fly straight up to it and present an easy target, allowing it to kill the lot of them by grabbing their helicopters and smashing them to the ground. Every single one of them ticks box b). Idiots.

Stupidity: Ashley Judd finally tracks her husband down and what does she do? She doesn't try to capture him to prove her innocence, she doesn't notify the police, she doesn't take his picture and send it to every police dept in the US, she doesn't even follow him to find out where her son is. Instead all she does is ask for her kid back. What was she going to do even if she got him back? She is still on the run from the law, with little money and resources and she doesn't even know if her kid even remembers her.
Suggested correction: As you said, she's on the run from the law. Why would she call the cops and risk going back to prison and losing her son again? Even if her husband was alive, she has no way of knowing what will happen to her. This was her best shot (especially in her mind) to getting her son back, thinking her husband would rather give up the boy's location rather than die; whereas height keep the boy's location a secret if all he was facing was possible jail time, if that.

Stupidity: When Flint Marko is escaping from the police, he climbs a chain link fence into a test facility. Besides having a chain link fence, there should have also been security cameras around the area as well as guards to prevent anyone from trying to get in. Plus, when the scientist notice on their computers that there's an increase in mass, one of them simply assumes it's a bird and then they continue their experiment. Instead of making assumptions, they should have halted their experiment and have someone take a look to see what caused the increase of mass.

Stupidity: John, the guy who taught Chucky the voodoo spell is confronted by Chucky later on in doll form. When things don't go how Chucky wants, he finds a Voodoo doll of the same guy just lying around and uses it to torture him. So this idiot who knows Voodoo and what it does, happens to have a Voodoo doll of himself just lying around? Yeah sure, that can't go wrong at all.

Stupidity: When Cathy, Chris and Carrie go into their late grandfather's room, they discover a copy of the grandfather's will that states that if it was ever discovered that Corrine had children, she would lose everything. Had they taken the will to their mom's wedding and showed it to her fiance, they would have been able to expose the scam much quicker. Instead, they take the dead mouse Fred with them and show it to everybody. What good would a dead mouse do when a will has more leverage?
Suggested correction: We never see them put the will away. It's possible one of them had it in their pocket during the wedding scene, but they just never showed it because A. Showing the will would have given motive for their mother to want to kill them, but not have proved that these children were hers, and B. The dead mouse is a more visceral, hate-fueled move that matches Kristy's anger.

Stupidity: After Josh runs away from home after being turned into an adult, nothing seems to be done about his "disappearance." The only indication that he is missing is his picture on the back of a milk carton. There's no flyers about him missing. No mention of his disappearance in any newspapers or TV news about his mom saying that he's been "abducted" by a stranger. Even when Josh writes a letter home, he uses the actual address of where he's staying, but no cops turn up at his door after his mom receives the letter.

Stupidity: The Death Star comes equipped with a powerful tractor beam capable of capturing a ship the size and agility of the Millennium Falcon. Why don't they use it against the rebel fighters attacking them at the end of the film? Okay, Obi-Wan Kenobi turned it off earlier but I find it hard to believe that someone who has never before visited the largest, most complex space station in the Universe and who was previously unaware of its very existence can disable a fundamental security system but the people who designed, built and run the whole thing can't work out how to switch it back on. They should have no problems with this, considering the fact that Obi-Wan didn't damage it.
Suggested correction: Obi Wan disrupted the battle at a critical time causing much confusion. We could chalk this oversight up to "Fog of War" - that in the heat of battle it's normal for commanders to overlook obvious things and seem to act stupidly. It would also be reasonable to assume that the fighters were too close for the tractor beam emitter to target them.
This scenario would require every single person on the Death Star who was involved in the maintenance of vital defence systems not noticing that one of them had been switched off! Not ONE person noticed? Obi Wan did not disable the tractor beam during "the heat of battle." There was a considerable time lapse between his switching off the tractor beam and the climactic final battle, during which time it would have been switched back on. When the Millenium Falcon leavs the Death Star Han Solo remarks that he hopes that "old man" succeeded in disabling the tractor beam, implying that those on the Death Star would be trying to use it. Even then, they didn't notice it had been switched off? Not sabotaged, not disabled, switched off.
Good point. This was definitely stupidity on the part of the Death Star crew, but not stupid as a plot point. It does happen in combat regularly. In 1987 the USS Stark was hit by 2 Iraqi Exocet missiles after challenging a single fighter. The ships' Close-in Weapons System should have easily shot the missiles down, but the investigation showed that no-one had noticed that the system had not been turned on.
They didn't use the tractor beam when the gang was escaping in the Falcon because they WANTED them to get away. The Empire placed a tracking beacon onboard so as to be able to find the hidden Rebel Base. As to how the Falcon was snagged originally: yes, they had just exited hyperspace, but they were not relatively fast; they were preoccupied with the TIE fighter (incapable of light speed) and the small moon right up to the point they were trapped in the tractor beam (and realizing "that's no moon!"
Suggested correction: The Falcon was travelling towards the Death Star when it was caught in the tractor beam. The tractor beam was properly turned back on by the time it travelled to Yavin. The rebel fighters are too small and quick to be held in a tractor beam and there are so many of them so it would be near impossible to trap enough to make a difference.
As I have already pointed out, assigning technical limitations to a wholly fictional piece of technology is absurd. As to "flying towards the Death Star" - the X and Y wing fighters are shown doing just that. As for being too quick, the Millenium Falcon is decelerating from superluminal speeds when it is captured in the tractor beam. That's pretty bloody fast in anyone's books.
The key phrase here is "fictional piece of technology", there is no way to understand how it works. Any explanations is pure conjecture.
It's flat out stated by General Dodonna in the battle briefing that the Death Star's defenses are based around repelling attacks by capital ships, not fighters. The targeting may not be exact enough.
Actually, claiming a fictional piece of equipment can't behave the way you think it should is somewhat silly. The previous explanation that the tractor beam's limitations were the reason for not using it during the battle makes perfect sense.

Stupidity: Steve Trevor is the leader of a group of Allied spies, and they are traveling with a gorgeous woman who has shown to have amazing fighting skills and super powers, but they allow a group photo to be taken with Diana in her armor. They don't know who is taking the photograph nor what they intend to do with it. Their photograph circulating through a news publication or passed on to an enemy's intelligence service could compromise himself and the rest of his team, and they would absolutely know that. Undercover agents do not pose for photographs.
Suggested correction: The photographer is not a reporter, he is one of the villagers. The photo was not taken to be circulated through print media, it was taken by the villagers to commemorate the day they were liberated. There only appears to be one copy of the photograph (which Bruce Wayne finds and sends to Diana), so the likelihood of it falling into the German's hands is incredibly slim.
It does not matter who took the photograph or why, or what he chooses to do with it. Undercover agents do not pose for photographs.

Stupidity: In the scene where Billy, Stu and Sidney are in the kitchen (when Sidney finds out they are the real killers), they begin to stab each other as a part of the plan to fool the police into thinking they were almost killed by Sidney's father, whom they were going to frame for the murders. They were planning on killing Sidney and her father, so it makes absolutely no sense that they begin stabbing each other BEFORE killing Sidney and her father, especially since Sidney would be at more of an advantage of outrunning them should she have the opportunity to since they have both been stabbed multiple times.

Stupidity: When Anna, Velkan and the villagers successfully trap the gray werewolf in a huge cage, the villagers start firing on it. Anna says they need to use Velkan's gun because it has silver bullets in it. Since everybody knew they were fighting a werewolf, all of them should have had silver bullets for their guns.

Stupidity: Dr. Jekyll must take an injection to keep himself from turning into the murderous Mr. Hyde. Hyde obviously doesn't want Jekyll to take the injections because he wants to remain in control of the body. The time between when he begins to feel himself turn into Hyde and when he has fully transformed is ridiculously brief. Why then does he keep the syringe locked in a box in his desk rather than on his person at all times?

Stupidity: When Charley goes to Evil's house, he asks him how to protect himself from vampires. Since Charley is such a huge fan of Fright Night and watches it all the time, he should already know everything to protect himself from Jerry.
Suggested correction: Being a fan of horror films in general and watching Fright Night on TV doesn't necessarily give someone expert knowledge of how to fight vampires. In fact, not every vampire movie is consistent with rules (including this one) and it is far from stupid to consult a friend who knows more than you about the subject. Think about it like this: If you watched every comic book movie that was made and every TV show based on comic books, then found out Galactus was real and you had to fight him, you wouldn't ask your friend who was a comic nerd for advice?

Stupidity: When Johnny is captured by Roarke and his followers, Danny gives him the power of the Ghost Rider back. Roarke knows what Danny is doing, but doesn't order his men to stop him, or even attempt to stop Danny himself.

Stupidity: The climax takes place during the launch of the "Buddi 2," a hotly anticipated tech gadget. The entire film has been leading up this point, and it's a big deal that it's being launched. And yet, there are no more than maybe 20 people waiting. Not a mistake per se, but totally unrealistic compared to the huge crowds these sort-of launches typically bring in.
Suggested correction: Bear in mind, this is just a cheap retail store in downtown Chicago; presumably, every major department and toy store across the country is having a similar event, so this opening would logically only draw people in the neighborhood with children the right age and willing to pay the opening-day price. Plus, we hear a voice on a radio warning of upcoming rain. The report is proven wrong since there's no rain for the rest of the scene, but even a warning of rain would ward some off.
I'll agree to disagree. I live in a relatively small, quiet town in upstate, New York, and events like new tech-launches (new iPhones, video games, etc.), movie premieres, anticipated book releases, etc. still regularly bring in pretty huge crowds at virtually every participating store. (Ex. Lines going out the doors and wrapping around the building.) Heck, I know someone who tried to get the last "Harry Potter" book opening night and couldn't because every local book store was packed completely full. So I have a hard time believing the crowd would be so small. The fact this movie also takes place in a pretty major city like Chicago is another strike against it.

Stupidity: When Lawrence begins turning into a werewolf in front of Dr. Hoenneger, his fellow doctors, Inspector Aberline and the guard, everybody just sits in their seats and watches the transformation instead of running for the door.
Suggested correction: We don't know how much cash it was, could just have been many 1$ bills and a few tens. So they probably would have needed more money at the beginning, and as they had to hurry for the train it couldn't have been possible for McCord to go for an ATM machine. They can use the card without danger until he reports it stolen (nobody knows at that time that McCord is helping them, so they wouldn't track down his credit card, until he reports the theft) So it's not even a character mistake as he thinks they'd be safe to use it in the next 24 hours. His warnings are for after the 24 hours, when it is reported stolen. And anyway, they need the credit card so that Jordan can get back into the facility.
Ronnie Bischof