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: There is a scene about a null hypothesis proving Cassius is the killer. Nearly everything is wrong in this scene. Statistically, you never prove a null hypothesis true. (01:23:11 - 01:24:22)
Stupidity: I seriously doubt that any Mexican Mafia cartel operating here in the U.S. would waste their time eliminating two simple patrol officers. There's nothing to gain by doing so, and it would bring a war between themselves and the police, which in return would bring hundreds of arrests of key members, drug busts, raids of their operations within Southern Cali, etc. They wouldn't risk their business taking millions of loss of revenue all to kill two patrol beat cops.
Stupidity: So he can rescue his wife from slavery, Django comes up with a plan to buy Candie's most expensive fighter and then get him to throw her in for free. Why doesn't Django just offer to buy her directly? Surely there was some amount that Candie would agree to. Even racists like money.
Suggested correction: You missed the point of the plan. They knew if they went in asking to buy Broomhilda directly, Candie would set the price too high. They feigned interested in his best fighter and would get him to throw in Django's wife at a nominal price. They would then just pay the nominal price for Broomhilda and back out of buying the fighter. It's only when Candie is told Django and Broomhilda know each other did he raise the price for her.
Yes, Candie, not Candle. Stupid typo on my part. I disagree with the correction though in the sense of why would Candie raise the price before knowing that Broomhilda was Django's wife? You yourself said in your correction that he only did so when he found this out. They could still have offered to buy her initially.
Because if they didn't feign interest in buying a fighter, Candie wouldn't have even invited them to his place. So the plan was to get him to throw her in for free, rather than risk him setting the price too high (or not even negotiating at all). Candie even figured out what their plan was.
Stupidity: Detective Loki checks in on Father Patrick Dunn and finds him passed out drunk. Dunn is a registered sex offender and drunk, but Loki goes in without backup or further plan. Yes, he had probable cause to enter the house once he saw Dunn passed out on the floor; however, he further explores the house and finds the hidden door behind the fridge. He then enters the basement without calling for backup, without notifying anybody else where he is at, and leaving himself at risk to be locked in. (00:30:35)
Stupidity: When they are in Italy on the boat, they find out they need to go to Montecarlo in order to reach Switzerland. They have a chopper. Italy is right next to Switzerland. It makes no sense that they would take a boat to Montecarlo to get to Switzerland, especially given the weather they'd have to sail through.
Suggested correction: We don't know where in Italy they are. If they are all the way in the south, there is no way a helicopter could make it to Switzerland on a single tank. Then he would also have to consider clearance for airspace, where and how to refuel etc. In short, sailing to Monaco and flying to Switzerland from there is much easier.
Clearance to dock in Monaco is needed if you sail with a large ship. Same trouble than air clearance. Using a helicopter is still faster, even with the eventual refuelling. Switzerland via Monaco makes no sense. They would still need to use the helicopter or a car from Monaco on.
Stupidity: Liv was a graduate psychology student when she met Bill and, after marriage and being physically abused, knew that the leaving Bill put her in a (potentially) very dangerous situation. It is best if the abuser does not know where the victim is "hiding" after separation, but Liv brought along Carol to pick up the kids - and they were going to be staying at Carol's house.
Suggested correction: She brought Carol along as a chaperone/protection when she picked up her kids. She didn't announce to Bill that that would be where she was going to be staying, she only told her kids that when they had already driven away from the house. Bill didn't seem to know who Carol was anyway. Even if he did manage to find out where she went, she could have easily got a restraining order against him.
It is more likely that she brought Carol along for emotional support and to act as a witness. If she were looking for protection, she would have used a police escort. It was implied they were going to be staying at Carol's, but, even if not, Carol's presence offered Bill a hint of where to start looking for Liv, and there should not be any leads. Liv unwittingly put Carol in a potentially dangerous situation - if Bill went to Carol's looking for Liv, and Carol truly did not know where she went, Bill would insist that she did and threaten or do worse if Carol didn't tell him. Remember how Bill drilled all the kids about where Liv went, checked their phones, accused Sam of knowing more, then got them into the car and drove like a maniac? Bill has a temper and propensity toward violence (at least when drinking, which he did everyday). Court orders take time to get, but are not very effective. Numerous women who had restraining orders against abusers ended up six feet under.
Stupidity: In the exciting denouement when the SS company approach the ostensibly disabled Sherman, the SS would have just walked around it. A burning tank was a common occurrence. I doubt they would start climbing on it and they certainly wouldn't start charging at it individually as to get mowed down. The SS were well trained units. Such stupidity is unlikely.
Stupidity: When she is getting the boots out, why is she sleeping outside when there is a fully covered wagon right there? (00:10:00)
Stupidity: With the threat of strangulating Jess, Garriga coerces a false confession from Nicky about the complicity of Jess. Garriga then laughs, calls Nicky out on it, and points out the confession's deficiencies. The film treats the whole scene as an astute reveal à la Sherlock Holmes! Nobody notices, let alone points out, that a coerced confession is worthless. In reality, Garriga would feel very stupid because he almost murdered someone. For the same reason, Jess must feel very angry.
Stupidity: The chef/cook of the house has his rifle, and he knows Morgan lost control and pretty much killed everybody on the premises. He comes face to face with her, but he lowers his rifle instead of taking the subject (Morgan) out with a shot. There is no logic here but to only pro-long the film. There's no reasoning with a scientifically created subject which is killing everybody it comes into contact with. (01:09:00)
Stupidity: When Doss buried the wounded soldier, leaving one eye out made no sense. It did nothing to help him. All it did was make it easier for the Japanese to spot him. It would've made sense to leave his nose and/or mouth out, so he could breathe. He did not need to see.
Suggested correction: A person who is unable to see is more likely to panic. When Doss buried the wounded Marine, he asked him to take a deep breath and trust him. By leaving one eye open, it allowed him to see the gravity of the situation as IJA soldiers walked by and maintain eye contact with Doss who hid under a dead Marine. After the suspicious IJA soldier bayoneted the body over Doss, he looked directly at where the wounded man was buried and kept walking. It was a crude method, but it likely saved them both.
Stupidity: When Sook-Hee walks into Hideko's bedroom before the two of them have sex, she slides the door open when going into the room and never closes it behind her. Once the two of them are in bed together and when they have sex, the door is left the way it is and never closed. Considering a sexual relationship between the two would have been completely forbidden, and, if they were caught, would likely ruin the plot to steal the inheritance money, it seems very foolish of them to ignore the open door, especially taking into account there are other people inside the mansion who could walk by at any moment. (00:41:30)
Stupidity: During the movie, the bad guys keep the main character alive and free to roam the facility at will (even if they made him sign an incriminating form at the very beginning stating he's an inmate) doing absolutely nothing to restrict his freedom till the very end - he even retains personal effects like his broken Rolex and lighter, his wallet full of cash! He breaks into every forbidden area, picks up fights, damages property, escapes multiple times and 'corrupts' the person the whole facility is built for. He is worth absolutely nothing to them and has nobody waiting for him or that will look for him.
Stupidity: At the end of the movie during the shootout. Cops would not engage in automatic gun fire with dozens of civilians in direct cross fire. Why not get a chopper and chase them down a bit maybe in an open area with fewer civilians? Then maybe engage in gunfire.