Deliberate mistake: At the end of the movie Rocketman shows his lady friend a space blanket, out of which he states he made something: ballroom dancing outfits. The difference in the material is just too obvious for this not to be a deliberate mistake. The outfits aren't the slightest bit related to the foil they were supposed to be made of.
Deliberate mistake: In the famous sequence where the pumpkin turns into a carriage, the fairy godmother stands behind it waving her wand and doing the magic. First mistake: After the transformation, the fairy godmother is stuck in freeze frame with her hands up in the air for the entire time when Cinderella is saying how lovely the carriage is. Another mistake occurs when it cuts to the fairy godmother (after the freeze frame), because her arms are suddenly down and she is moving and talking to Cinderella.
Deliberate mistake: When Leota is in the front seat of the automobile, the air bag is still full. Air bags will deploy and then immediately deflate to prevent people (or women in crystal balls) from being trapped. (01:10:45)
Deliberate mistake: When Scrat's coconut falls from the tree, it has already had its husk removed. The directors confirm this on the DVD commentary. They may have been worried that a lot of their audience would not recognise a coconut with its husk on. (01:11:45)
Deliberate mistake: In the film, Martha Jefferson visits Thomas in Philadelphia. While this is factually inaccurate (she was actually at home recovering from a miscarriage), it was changed for the sake of drama.
Deliberate mistake: While the mouse is walking on Dumbo's trunk, there is a jump in the animation. He's facing Dumbo at one point, then all of the sudden he is in a different position and is facing the other way (this all occurring in the same shot). Look for it before the mouse says, "Dumbo, the great!"
Deliberate mistake: At the start of the film when the commentators are explaining the tie situation between the 3 cars the green arrow to the car is out of alignment and misses the car, instead pointing at the track. Pixar Creative Director, Jay Ward, who is this film's team manager (as well as art coordinator) has stated that this was deliberately done as a joke, for fun. It's a little bit off, in the same way that Chick Hicks is a little bit off. This is the video with Jay Ward explaining: https://youtu.be/ZkJre-eC-zE?t=25.
Deliberate mistake: While the rock n' roll musical is ending, it shows the hot air balloons in the background and it shows Dave up close. He talks to himself confused, trying to figure out if he really saw his boys there or not. But if not being able to notice, wouldn't he at least hear them singing in the background as well as we can? Also, before, while Alvin and Britany were dancing together, he was trying to get to them before the two bad guys could, as if he knew for sure they were his boys and that those guys were out to get them.
Deliberate mistake: Frank Beardsley moves his family into an old, defunct lighthouse, and subsequently makes a project of restoring the rotating lamp and actually running it. But lighthouses are navigational devices. Each one in use has its own unique, catalogued period, which identifies it and therefore helps a distant ship determine its own position. By running a "phantom" lighthouse, Frank, a career Coast Guard officer, risks confusing ships' navigators at sea. No real nautical officer would do such a thing.
Deliberate mistake: When the boy jumps on the Police motor tricycle and his father jumps on as pillion passenger it is obvious in the subsequent scenes that a small but adult stand-in is riding the trike.
Deliberate mistake: The Benchwarmers originally had only three players, and then only one who could actually hit. Despite this, none of the (supposedly competent) little league coaches chose to simply walk all the players and force an out.
Deliberate mistake: Many times, Pocahontas' hair blows in the wind, even though nothing else moves in the shot. From the way her hair moves, the wind should be strong enough to move something else, but not even John Smith's hair moves.
Deliberate mistake: In the scene where Mr. Bean is hitch hiking, right before the shot where the truck runs over the wooden box, there is a wide angled shot. The road is very long and it is clear that there is no truck coming. In the next shot, the truck suddenly zooms by from the right of the screen. This can also be seen on the trailer. (00:44:30)
Deliberate mistake: When Penny is loaded onto the ambulance at the end, her gurney is rolled straight in. This is wrong, the paramedics will collapse the wheels and slide the gurney into locks to hold it still during the drive. It was done this way since Mittens and Rhino were hiding in the collapsible section.
Deliberate mistake: When Eric's ship blows up, his statue bobs up and down. A statue this weight would not be able to bob up and down for even a second. It would just sink straight to the bottom.
Deliberate mistake: Foils, rapiers and other fencing weapons did not appear before around the 16th/17th century, yet the main characters (in an approximate 8th to 10th century setting) use them extensively. I know that back in the days when the movie was made, the swashbuckling genre was quite popular, but it still is a reality error.
Deliberate mistake: When Bastian comes running up the stairs by the harbour, you can see a black couple on the right. The woman is wearing a grey coat with a black vest and a white shirt. The man is wearing a black coat, black shoes and white socks. When it cuts to Bastian running across the street, you can see the exact same couple wearing the exact same clothing crossing the street, but this time they are not walking together. The extras were used twice. (00:11:10)
Deliberate mistake: It's not possible for Chance to have been able to launch the cougar off the cliff with just his own weight.
Deliberate mistake: There was no possible way for Edith to still be alive after the spiked coffin closed in on her. There are spikes on the doors and at the very back and sides of it, and she couldn't have squeezed in to brace herself. Probably done for obvious reasons, but still a mistake nonetheless.
Deliberate mistake: During Lansbury and Dr. Brown's dance scene under the water, the drawings behind them (with couples of fishes sitting on their seats) are a still drawing, no animation at all.