A plot hole is not always a sign of shoddy work. The viewers are simply more observant than the filmmakers.
1. The Avengers, 2012
Fan-favorite Loki in The Avengers can transform into any person, superhero, or God and gain complete control over people. His powers helped him undermine the S.H.I.E.L.D. from within, which is wonderful of him — but why didn't he get right into the head of the S.H.I.E.L.D. Director Nick Fury? Then he'd have the job done without much sweat.
2. Avengers: Age of Ultron, 2015
The mutant twins Wanda and Pietro can't stand Tony Stark. They got a guaranteed chance to kill the guy, along with the rest of the Avengers. But instead, the twins cause their enemies to hallucinate and… that's it. It's like meeting your worst enemy and getting them drunk on absinthe, to no particular purpose.
3. Lara Croft: Tomb Raider, 2001
Lara Croft showcases a typically dumb Hollywood plot. The villains hunt for an artifact split in two pieces. Lara Croft has one of the pieces, right from the start. All she has to do is destroy it, and the villain will never be able to assemble the artifact, right? However, this thought never crossed Lara's mind during the whole hour and a half of the movie.
4. Gremlins, 1984
When we watched Gremlins as kids, we didn't think critically about one of the key rules for keeping a gremlin: "Don't ever feed him after midnight". So what does this "after midnight" mean anyway? One hour past midnight, six in the morning, three in the afternoon — the whole 24-hour cycle is "after midnight"!
5. The Day After Tomorrow, 2004
This film contains another stupid plot contrivance. Trapped in the New York Public Library by severe cold, the characters burn invaluable books only to stay warm. Apparently, nobody told them that wood works perfectly well as fuel, and there are hundreds of wooden cabinets, tables, doors, shelves, floorboards, and chairs around.
6. The Fly, 1986
Here's an interesting point to ponder. If a human and a fly get into the teleportation device, the result is a fusion of their DNAs. Meanwhile, humans carry hundreds of different DNAs that belong to the microorganisms living inside our bodies. So why doesn't teleportation in The Fly fuse human genes with those of an amoeba or a fungus?
7. X-Men, 2000
Professor X uses a device called Cerebro to find any mutant anywhere on Earth. Magneto doesn't want the professor to find him, so he makes himself a Cerebro-proof helmet. Makes sense so far, doesn't it? Well, yes, but Magneto hangs around with his gang of mutants that Professor knows and can track very well — and they aren't wearing any helmets!
8. Pacific Rim, 2013
The film claims that the Gipsy Danger Jaeger is invulnerable to electromagnetic pulse because it is analog and powered by a nuclear reactor. But actually, the nuclear reactor is itself a device packed with electronics, and the view of Gipsy Danger's control cabin reveals more than just cast-iron levers.
9. Planet of the Apes, 2001
We are clearly told that the planet was completely uninhabited before the spaceship with monkeys and humans landed there. So where did the horses come from?!
10. Kong: Skull Island, 2017
An American pilot has spent 30-odd years on an isolated island and has been reported missing all that time. Back in America, he simply hails a cab and gives his wife's address. So in the long weeks he spent on the boat getting back to the US, no one bothered to send a radiogram to tell about his return? The guy should've received a whole welcome ceremony with the military, journalists, the orchestra, and his wife, besides thousands of onlookers, greeting him on the shore.
11. Ocean's Eleven, 2001
The film's director, maestro Steven Soderbergh, admitted publicly that he has no idea how and at what point the thieves were able to substitute Bellagio money for worthless pieces of scrap paper.
12. San Andreas, 2015
It's hard to decide if it falls into the category of plot holes or just screenwriters' stupidity. Does it make sense for a rescue-chopper pilot, a fearless American hero, and patriot, to grab his service helicopter and rush off to save his family at a time when the whole country is in danger? That's what Dwayne Johnson's character does throughout the movie.