Adaptation Correction

Any author, no matter how famous, can make a mistake, and many are the cases of works that contain mistakes of one kind or another. And adaptations can change a work in a way which enrages purists. But sometimes, if the work gets a chance to be adapted to another medium, the adapters might notice, and the adaptation can be used to fix the mistake, at least in the adapted version.

A fix that causes another problem can lead to a Voodoo Shark.

See also Translation Correction.

Anime/Manga

 * In Jojo's Bizarre Adventure part 3, the original manga had a menu that included the Chinese characters for "fried duck" with the reading for "fried frog". This was fixed when this was adapted into episode 4 of the second season of the TV series.

Film

 * In the book of Goldfinger, there is a plot to physically steal the gold of Fort Knox (which the movie Bond points out is impossible) which includes poisoning the soldiers through the water system before they can react to such a slow method and using a nuclear bomb to open a door with everyone suicidally close. The movie changes the scheme into a genuinely ingenious plan to have the poison as a gas sprayed from a quick aerial pass over the fort and then Goldfinger's troops raid the fort just long enough to use a high power laser to open the vault building's door to place a nuclear bomb in the main vault. Then the villains get away for the bomb to detonate and whatever gold survives the blast would be radioactive, and thus worthless, for decades while Auric Goldfinger's own gold's value jumps at least tenfold.
 * The movie Fantastic Voyage contained a plot hole: the shrunken submarine was destroyed, and therefore didn't return to normal size inside the patient (which would kill him)--but destroying isn't disintegration; enlarging debris would be as bad a problem as an enlarging submarine. When Isaac Asimov novelized it, he had a blood cell engulf the debris so that it could be taken out of the patient safely.
 * In The Wonderful Wizard of Oz, the Scarecrow becomes King of the Emerald City after the Wizard departs. The sequel, The Marvelous Land of Oz, introduces the idea that there was a royal family who ruled the Emerald City before the Wizard took over, and when the Scarecrow is deposed by General Jinjur's army, Glinda refuses to help restore him to the throne because he has no more right to it than Jinjur has—even though she approved of him taking the throne at the end of the previous book.
 * In the animated series The Wonderful Wizard of Oz (anime), which adapts both books, Glinda explains that when she approved of the Scarecrow becoming King she thought the royal family had died out, and only since then had learned that the rightful heir had been hidden away but was still alive.
 * The Trope Namer for Voodoo Shark is, at least, an attempted example. The novelization for Jaws: The Revenge tried to justify the shark's unrealistic actions in the movie by adding a voodoo curse into the story.
 * The film adaptations of The Hobbit have had numerous plot changes, many for the sake of padding, others to seal plot holes within the book. Most notably, in the book the dwarves' plan to have one burglar sneak into Erebor and steal Smaug's entire horde of gold was implausible, so in the film they were specifically after the Arkenstone, which would have given Thorin the authority to rally the Dwarves to take back the kingdom.
 * On the other hand, stealing a sleeping dragon's treasure bit by bit is safer than trying to poke the dragon with a sword. Also, in the book Thorin, despite his royal blood, isn't portrayed as such a great planner. The problem with the movie's take is that a system of government based on possession of a single gem is implausible, especially when said gem isn't even that old, all things considered. Why would all the other Dwarves change their loyalties and risk their lives against a legendary dragon because of one successful theft?

Live Action TV

 * The original Star Trek, when it introduced tribbles, had Spock say that the number of tribbles in a bin, assuming each one has ten offspring and taking into consideration other factors, was 1,771,561. This number is equal to 116, which is to say, it assumes each one has ten offspring without taking other factors into consideration.  The novelization by James Blish changes it to a different number that could plausibly be considering unknown other factors.

Multiple
In this post, Peter David describes how he made corrections to the novelization for Return of Swamp Thing and the comic book adaptations of Star Trek V and Star Trek VI.