
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: When Bobbi Jo sees Ash's severed possessed hand holding her hand, she freaks out and runs out of the cabin and then gets killed by possessed trees. While it's certainly natural for her to be terrified, why would she run AWAY from where all her friends are and go off by herself?
Suggested correction: She is a civilian in a blind panic, and even people with actual training have done dumber in panics (e.g., choking firefighters run away from other firefighters who could help them). She also has no idea how dangerous the woods are at this point; she walked to the cabin just fine and only saw scary things inside it, so she thinks she'll be fine if she just runs from the cabin.

Stupidity: After Casi changed the tracker on the Navigator, he was sneaking between vehicles to get out of the tow pound. The Whale came and stood in front of the two vehicles Casi was between. Casi stood up and, instead of turning around and running away, rushed TOWARD The Whale in an attempt to get past him. The Whale, much bigger, threw Casi against a vehicle and then onto the garage floor. (01:03:34).

Stupidity: It's mostly a fun absurdity, but it is somewhat contradictory to showcase the Ghostbusters being featured as the cover story of every major publication and news outlet, and yet to get help not only they put an ad on the newspaper, but a single person applies for the job (which is all it took for them to accept).

Stupidity: Dr. April (as well as her patient Mrs. B) is nonchalant when her young nephew Zeke brings his dog hit by an automobile into the hospital. Dr. April, continuing to hold her clipboard, tells her nephew she is "not that kind of doctor" and "what you need is a doctor for animals." The doctor-aunt could have at least taken the dog from Zeke's arms to ease his panic and see if there is something obvious she could do to help the dog. Instead, she walks out with Zeke still carrying the dog. (00:02:45)

Stupidity: When Bob is fighting one of the Russians, Tatiana could have kidnapped Nota but instead stands beside her and watches. (00:52:05)

Stupidity: When making apple sauce, just slapping a paper lid on the jar (instead of canning it properly) , would soon result in the jars turning to mold.

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: 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: John Candy was being dragged by the speedboat because he was holding the bar when the boat took off. It simply never occurred to him that letting go off the bar would have solved the problem (Of course then you wouldn't have had the speedboat scene at all but it's still pretty dumb).
Suggested correction: Characters doing stupid things doesn't constitute a stupidity entry. That was part of the joke, that Chet spent all the time telling his son to remember to let go of the rope if something goes wrong, but then forgets his own advice in the heat of the moment. People do stupid things in real life all the time.
Well how does this not count as a Stupidity then? You just said it was and there was no need for him to stay holding onto the rope.
Stupidity is basically a minor plot hole, something small that doesn't rise to the level of an plot hole entry. Characters are still allowed to do stupid things though if it's not a plot hole (otherwise everything Lloyd and Harry do in all the Dumb and Dumber movies would be stupidity entries).

Stupidity: After all the singing and dancing at the Tent Revival, Lt Elizondo yells at her fellow officers "It's a Trick, they've brainwashed the Captain, get 'em." Considering her and everyone else just witnessed the Captain float into the sky surrounded by fireworks and miraculously change into a black suit her "brainwashing" assumption is truly stupid.

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: In the bar scene, Jack gets into a fight with a guy he busted a few years back, then Reggie turns to the bartender and asks for a gun. The bartender hardly hesitates and hands it over. There is just simply no scenario where a bartender would hand a loaded gun to a patron they had just met.

Stupidity: There's no reason for the Foot Clan to confront the Turtles at TGRI and show them that they are in possession of the last canister of ooze. They already have what they came for and nearly lost it by battling the Turtles. Even if they wanted to kill two birds with one stone and see if they could defeat the Turtles while they were there, they still could have sent one of the soldiers back to headquarters with the ooze before revealing themselves and not risk losing it in the fight.