Stupidity: Two oil rig workers were looking at two young ladies in bikinis who were sunning themselves on a boat/yacht. One oil rig worker said, "That's where we should be right now. With them, enjoying the sun, instead of baking in it." Both men had double layers on - a jacket or sweater over a jersey or T-shirt - and one man was wearing a tossel cap. Even if it gets cold on the rigs at night, they did not need to be dressed in warm attire during the sunny daylight hours. (00:10:35)
Stupidity: Bond has been shot at and hunted down by armed men and dogs. He must conclude his life is in danger, and yet after Bond despatches the armed man in the creek who is carrying a British Sten submachine gun, he fails to pickup the weapon which has far superior firepower to his small calibre hand gun. Had he done, so he may well have saved Quarrel and avoided capture.
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.
Stupidity: Long after the Marine Life Institute has closed for the night, the recording of Sigourney Weaver welcoming visitors is still playing.
Stupidity: At the end of "You're Welcome", Maui puts Moana in a cave and placed a large rock blocking the only known exit. This means, as far as Maui knows, he's trapped a human in a cave with no food, water or exit as he didn't know Moana could make a very lucky escape. Basically Maui was going to leave Moana to starve to death so he could take her boat.
Suggested correction: This isn't a mistake. Maui doesn't care about anything other than escaping at this point. He even says, Without his hook he is nothing. He's not interested in returning the heart at first so even though he is a demigod, he has lost interest in being good. Another example is when he leaves Moana to face TeKa on her own.
Stupidity: Spoiler alert. After the son makes it out, he could get a rescue team to get his dad by going in where he came out.
Stupidity: Simon has told his wife Christine to never go into his shed/lab where he has dinosaurs chained. Christine is looking for her son Mark. Instead of searching the house (and finding Mark in his bedroom) or asking Simon to check the shed, Christine goes into the shed and is killed by a raptor. (00:02:30 - 00:04:58)
Stupidity: In the shuttle, when the fountain pen is floating in zero gravity, the flight attendant grabs the pen and puts it in the pocket of the sleeping passenger. She doesn't put the cap on. She puts it in his pocket nib down. Even though there is no gravity, the capillary action of the nib touching the shirt will pull the ink into his clothing and stain his shirt and jacket. (00:19:40)
Suggested correction: Who said it's a fountain pen? 2001 is set in an imaginary future with imaginary technology, one of which might be leak-proof pens.
Stupidity: Since we get frequent POV shots from their eyes, we see exactly what the creatures hunting Venom see. Even when the Codex disappears from their view, they can see distinctly Venom's shape, and they have no problem using their appendages and brute force against any and every creature. There are moments in the movie (such as the scene in Vegas) when the Xenophage just stops for no reason; even if the big blinking thing is gone, you can still see the shape it was attached to.
Stupidity: At the end of the plane chase Bond fails to finish off Hinx. Regardless whether he thinks he's dead or not, with a licence to kill he should have made sure.
Stupidity: Jake uses several Loops and travels all over the world in order to get back on the boat at the end of the film. This was completely unnecessary as only the final Loop in 1942, which was available to him in 2016, was the one he needed to enter despite the fact that its nature should have prevented him from reaching 1943 anyway.
Stupidity: Kora and Gunnar arrive at the town to find the rebel Bloodaxes via a contact of Gunnar's. They literally see this contact being hauled out of a bar by bounty hunters who work for the Imperium...and then walk straight into the same bar and start openly talking about needing to find the rebels right in front of the bartender and other patrons, who for all they know are all Imperium-aligned.
Stupidity: The whole movie necessarily has to be filled with stupidity (we're talking about a 9 months kid besting 3 adults), but there's one part perhaps not so obvious and that may be related to a mistake about the ransom note. When the bad guys watch the news, it's obvious that their original plan failed, since they cannot retrieve the money at the designed drop zone, the police have been called and they'd need to rethink the whole operation. Yet they make no comment about it and don't seem bothered by that at all.
Stupidity: So if Harley Quinn drove the truck to blow up the plant, wouldn't she have had to drive through all the cop cars at the bar murder scene? We know it was the same street because the cop gives the necklace to the detective. (00:10:58)
Stupidity: When Donatello frees the professor, he gets his head in his visual range, and same goes for his thick inhuman hands, but he notices only when the plot says so, a few moments later. (00:52:50)
Suggested correction: The professor is in noticeable distress, likely from having been tied up for so long and hearing the fight between the foot soldiers and the turtles occurring just outside, so he isn't paying much attention to who is rescuing him at first; he just wants his hands untied and to get the tape off his mouth.