Stupidity: Liv and her five friends went to Willy's to set it on fire, but Liv insisted they first go inside to get the Janitor out. All were aware of the situation and danger related to the mass murderer and the animatronics, but Bobby and Kathy went into another room to "hook up." Kathy recognized the room as the one where the killers committed suicide and later saw movement, but she continued having sex with Bobby until he was attacked and killed. (00:38:48 - 00:42:02)
Stupidity: All that chaos going on at the end of the movie. Gun shots. Screaming. Blowing up police cars. Yet not one neighbor comes out to see what's going on.
Suggested correction: Gunshots and explosions going off at a neighbor's house isn't going to make me go and investigate. It's going to make me call the police and hide in my own house.
Stupidity: As the movie progresses, we see the deranged killer, Martin, collecting a dozen victims for his Human Centipede project and depositing the victims in a sealed chamber. Every time we see the victims, they are nude, face-down (always in the same positions on the floor), struggling and moaning and sobbing. However, their hands are only duct-taped behind their backs, and their ankles are duct-taped. There is nothing to prevent these victims from rolling over, sitting up, standing, and even assisting each other to escape. Yet they never change positions or attempt to escape.
Suggested correction: The entirety of the film, save the opening and closing scenes, is intended to be a disturbed fantasy of Martin. As such, any inconsistencies or character mistakes such as this can be attributed to Martin's deranged mind. He is fantasizing about creating a centipede of his own and his fantasy is not detailed enough to include an explanation as to why his victims can't escape or help one another.
Stupidity: Zoe and her team go into the medical university to get medical supplies for their camp and Lily. As they are leaving, Zoe sees the Epidemiology room where she used to work and waits, letting her team run off leaving her behind and then goes into the room alone so she can get pictures and some small bottles. Letting her team run off leaving her by herself in a zombie infested building in a city without telling her team that she's not following them. And this did lead to her having to shoot at a zombie that jumped her, alerting the other zombies around, and is what got Frank killed and lead to the smart zombie stowing away on their Hummers and sneaking into their camp. (00:29:35)
Stupidity: The whole movie happens for unbelievably convoluted causes. Despite their friendship and the simple fact that he still runs an occult shop (showing that he's not exactly insensitive to the past), Ray in years never spent a single moment to check on Egon's whereabouts, which he knew, or listen to him. The city has Shandor's name all over and any cursory investigation would have unveiled the connection. Assuming of course that Egon turned into such a lunatic he couldn't do the namedropping himself.
Stupidity: Why didn't they take out the crushed hand guy while the creature was fumbling inside the glove? Plenty of time to do it. Why did no one use a knife to stab the creature?
Stupidity: While Mr. Butler was upstairs taking a shower, Lucas goes into his house, kills his wife, and takes the baby to the school (into Mr. Butler's classroom). Lucas wanted to take away Mr. Butler's family, so all he needed to do was also kill the baby at the house (or leave the dead baby outside on the porch for Mr. Butler to panic while searching). Lucas could have left the house without getting caught for committing a double murder; instead, he keeps the baby alive and assumes Mr. Butler will know he took the baby to his classroom. (01:17:53)
Stupidity: Knowing that the Klowns' noses are their weak point from previously shooting them, Dave doesn't bother to shoot the giant Klown at the end with his pistol, instead waiting to be almost crushed and finally popping it with his badge pin.
Stupidity: Soon after the new art therapy instructor Anna arrived for her first day at the mental hospital, Leena - the most dangerous patient - was not in her room and nobody could find her. The hospital went into lock down and the doctor took Anna to a room. Without first looking in the room, the doctor said, "Do not leave this room. Don't worry, you will be safe here and we'll come back after we found her" and then locked Anna inside the room - with Leena. (00:03:36 - 00:04:41)
Stupidity: In the opening scene, when Jason lunges at Whitney, the screen cuts to the title card with his machete swinging 12-6 just inches from her skull. This makes it hard to believe he had a change of heart and pulled his windup before splitting her head in half.
Stupidity: During the final battle, Gomm kills one of the rednecks by sticking his tentacles into the man's eyes. However, the entire scene is shot very sloppily. The man has his gun trained on Gomm for almost 10 full seconds, and just stands there while the tentacles come out slowly, Gomm laughs, and then the tentacles shoot forward. Given the amount of mayhem and creatures, there's no reason for the redneck to have not just shot Gomm during that period of time.
Stupidity: The location of the small hole near the bottom of the wood-trimmed wall where Everette passed Sharyn a note and pencil would have taken much more time and effort to accomplish compared to merely penetrating the wall a little higher (where there would not have been wood trimming/baseboard on both sides). (00:10:00)
Stupidity: During the ghost chase montage, why would Velma look for her glasses with her hand in midair instead than on the ground? No matter how nearsighted you are, the closest wall, or obstacle, is meters away and you'll never find your glasses anywhere but the floor. She does it for a longer time than anyone would. (00:52:40)
Stupidity: How would a devout catholic like Angela not believe in the devil, as she tells Constantine? Makes no sense.
Suggested correction: Some Christians don't believe in the literal personification of the Devil. They see him more as a metaphor for all human sins. So according to them, the Devil is not something to blame evil on. Everybody has God and the Devil in them.
Stupidity: Charlie set her mom's blouse sleeves on fire and mom/Vicky just stood in the same spot, holding her arms (burning sleeves) out in front of her until Andy came and smothered the flames with a blanket. Even children know to "drop and roll" or put fire out by smothering it. (00:22:56)
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)