Deliberate mistake: During the scenes where Maverick is flying the Darkstar spy plane, his helmet is lit up on the inside, so we can see his face. In reality the light would be reflecting off the plexiglass, meaning we would not be able to see his face, and he would not be able to see at all.
Deliberate mistake: The baddies somehow manage to place the net under the two humongous ships by simply digging with their shovels in a matter of minutes, when they would need a bulldozer and several hours instead.
Deliberate mistake: Some clothes were interchangeable from one character to another (or within a character over time), despite their obvious differences in sizes/body frames. Hazel, as a much heavier senior citizen, was still able to wear her "lucky" carnation pink coat that fit her 58 years earlier when she was a skinny young lady. Hazel was also able to switch coats with Margot, who had a much thinner body. The coat on Margot even looked form-fitting afterwards. Kip's tuxedo did not look too large on Griffin. (00:45:20 - 00:49:50)
Deliberate mistake: While walking bare-footed in the barn looking for RJ, Wayne does not raise his feet very high - that is, until he is about to tramp on the nail that is perpendicular to the floor. If Wayne had kept walking like he had been, he might have bumped into the nail or object holding it up, but not got punctured by the nail. (01:06:40)
Deliberate mistake: In the dark, dilapidated house, Margaret asked Abby, "What's that?" and Abby was able to illuminate a large portion of the room with a disposable lighter. (00:16:35)
Deliberate mistake: One of the first shots in Greece shows Benoit Blanc and Lionel standing on the pier. As director Rian Johnson himself says in an interview for the Vanity Fair Youtube channel, "Matches nothing else in the scene lighting-wise, but it's gorgeous soooo...who cares." (00:13:30)
Deliberate mistake: While roasting marshmallows, Henry's marshmallow caught on fire with the flame shooting about 6", then a foot+ high. A marshmallow subjected to such intense heat/flame for many seconds would not be stuck to the stick and stay stuck with repeated forceful flicking or "whipping" of the stick like Henry did. When the marshmallow finally flew off the stick and landed on a camper's head (higher than would be expected), it would be small/hard/charred, not large and still soft/white in the middle. (00:35:03)
Deliberate mistake: Bill's back is some distance from the middle gap in the curtains, but an exterior view of him hugging Ellen captures their faces as if they are standing closer to the window and the gap in the curtains is wider. (00:32:45)
Deliberate mistake: Blood does - but should not - drain out of deceased Mitch's mouth when he is placed on the couch and his head falls over because Oliver gets up. (00:30:10)
Deliberate mistake: Richard falls (or is pushed) into the lake, and a loud splash is heard. However, as he pulls himself onto the deck, no water drips from him. But there is already a large wet area further onto the deck when the sheriff tosses him. (00:18:05)
Deliberate mistake: Due to some unknown factors (e.g, time of night), the doves' or pigeons' behavior in the boarded-up building falls short of "factual errors." Doves respond to sound and movement, so would have flown to higher spots when Alex was at the door. Doves typically roost up high, so it is questionable why they were at floor-level. If/when doves do sleep on/near the ground, they do so in a lighter mode (one eye open) and, when spooked, would have flown away at roughly the same time, not at intervals. (00:51:15)
Deliberate mistake: At the end of the car chase with Penguin Batman's car drives upon a ramp at high speed before the explosions occur but his car only appears flying through the air and landing 15 seconds after the explosions. That's quite a long jump. (01:23:33)
Deliberate mistake: Elizabeth will not be able to save Mateo from falling backwards into the fire pit by grabbing his hand or pulling him back after his whole body is suspended over the edge. (01:13:47)
Deliberate mistake: When Prince Henry was sitting on the porch, there was snow accumulated all along the inner side of the railing - but the attached perpendicular boards (about 4" high) on the outside should have blocked snow, or that amount of snow, from accumulating there. (00:42:30)
Deliberate mistake: Four hungry wild dogs are biting/eating at Virgil's abdominal area for some time, yet when the body is shown, some intestines are on top of his seemingly still-intact stomach - little, if any, of Virgil can be eaten by the "ravenous" dogs despite the length of time they are there. (01:29:00 - 01:30:13)
Deliberate mistake: There is one vertical board missing between the other parallel boards, but the upper half of the gap is wider and forms a "V" when Mark is videotaping Jenna (who is on the other side of the fence). The missing board, between two parallel boards, has a uniform width from top to bottom. (00:08:40)
Deliberate mistake: There isn't an accurately-positioned light source bright or close enough that can project striped lines - especially that wide - across Rockit's face while he is lying in bed. (00:07:00)
Deliberate mistake: A pot pie in an aluminium pan that just came out of the oven would be extremely hot, but Karen was not only able to tolerate it being shoved into her mouth, she was able to take a bite and hold the hot pie pan in her hand without getting burned. (00:09:44)
Deliberate mistake: The number of clicks (sounds) Christine made on the "text to talk" device did not match the total characters she typed. With few exceptions, there were a lot less clicks/sounds than there should have been based on the amount of letters/words she typed. (00:06:40 - 00:15:30)
Deliberate mistake: Considering the position of the surveillance camera (height and angle - almost parallel to the side of the building as well as to the sidewalk), plus the lens being indented within the outer frame, it would not have been able to capture a view of Redd on the sidewalk below like it did. (00:24:40)