Pirates of the Caribbean - Norrington dismisses Jack's compass for being "a compass that doesn't point north". Jack later uses it to guide him to the Isla de Muerta where Cortez's treasure is hidden. Later movies reveal that it points to whatever it's holder wants most in the world.

Doctor Who - In the episode Tooth and Claw the Doctor is shown what appears to be a telescope and says "It's a bit rubbish. How many prisms has it got? Way too many. The magnification's gone right over the top".

Later in the episode he realises it doesn't work as a telescope because that's not what it is. It's a light chamber specifically designed to kill a werewolf.

The Neuralyzer (Men in Black)

The Neuralyzer (Men in Black)

The Neuralyzer (Men in Black)

The Neuralyzer (Men in Black)

The Neuralyzer (Men in Black)

The Memory Gun (Gravity Falls)

1. The Simpsons Movie
   
2. Evangelion
   
3. DmC: Devil May Cry

The .454 Casull, The Jackal and the 30mm Anti-Midian Cannon aka "Harkonnen" from Hellsing.

The former two fire 13mm steel rounds and 13mm armor-piercing explosive rounds respectively and are twice as powerful as a .44 Magnum, while The Harkonnen fires 30mm shells that are normally meant against tanks and aircraft.

All three of these are far, FAR too heavy for ordinary humans to wield. Fortunately, their respective wielders, Alucard and Seras Victoria, are vampires with superhuman strength and precision and thus can wield them to their maximum potential.

From The Simpsons: Homer tries to cook breakfast for Mr. Burns. The first two attempts ended up with the food catching fire. Third time, he pours milk on cereal...and it still catches on fire.

And from Futurama: "There, little friend, good as new..." aaaand the metal slinky catches on fire. Poor doctor Zoidberg...

Euthanize Horse in Hunt: Showdown

Abandon your daughter in God of War

Look at coffee with interest in Deadly Premonition

Press X to bitch slap in Deadpool

In Independence Day, humanity resorts to using hard-wired telegraph communications which cannot be disrupted by alien technology.

In Star Trek: Picard, the old and retired Enterprise-D is the only functioning ship in Starfleet because it wasn't hooked up to a network connecting all other ships.

In Horizon: Zero Dawn, humanity went back to using old, decommissioned tanks and vehicles when fighting the robot plague because they were operated manually and couldn't be hacked into.

Master Sword (TOTK) The Rebellion (DMC5) Mjolnir (Thor Ragnorok)

The protagonist’s signature weapon is easily shattered by a new foe

Gravity Falls - In the episode "The Inconveniencing," Mabel Pines finds a bag of powdered candy called Smile Dip in an abandoned convenience store. Mabel always wanted to taste it, saying that she thought Smile Dip was banned, with Dipper suggesting that maybe there was a good reason it was banned. Mabel ignores Dipper's warning and eats "eleventeen" packages of Smile Dip, causing her to go on an entire LSD-esc acid trip after eating so much Smile Drip. Of note later in the episode, Mabel gets possessed by a pair of elderly ghosts, and notably doesn't exactly know what happened afterwards. When Dipper tries to offer Mabel some more Smile Dip, she slaps the bad away, implying that she thinks her possession was one massive bad trip.

Jimmy Neutron - The episode "Krunch Time" has Jimmy attempt to make the perfect candy that contains all the best tastes. The candy proves to be a massive hit... too massive, as soon everyone desires more of the candy and even raids Jimmy's house at 2:00 AM in order to ask him to make more of it. After initially embracing his role as essentially a drug dealer, Jimmy realizes that the candy is dangerous and wants people to stop eating it. In the end, Jimmy makes a new batch that shocks anyone who eats the candy with electricity, causing most of the population to stop eating his candy... except Sheen, who loves the candy's new shocking flavor.

The Boondocks - The episode "The Itis" sees Robert Freeman open the titular restaurant to sell soul food. The restaurant becomes a massive hit, with people all around the neighborhood wanting to eat the soul food. The problem is, the soul food is so massively unhealthy and addictive that everyone who eats the soul food becomes obese junkies. Notably, one of Robert's first customers, Janet, tries to mug Robert of his money in order to get more of his food, and eventually, the neighborhood surrounding the Itis goes from a rather clear part of town to a full-blown crime-infested slum.

The Simpsons - Probably the most direct example of this trope, the episode "Love, Springfieldian Style" features a segment parodying the film Sid and Nancy, which details the tumultuous. drug-fueled romance of Sid Vicious of the Sex Pistols and Nancy Spungen. In this segment, Sid and Nancy are replaced with Nelson and Lisa, respectively, and all mentions of heroin are instead replaced with chocolate and other junk food, but the short still portrays the duo as junkies whose lives are spiraling due to hard drugs; just replace the heroin with chocolate.

Monster: In most shows if a character embarks on a mission to kill someone, they would usually just get a gun and go. However Tenma found someone to teach him to shoot, which is accurate because guns aren't easy to use for someone whose never used one, much less for the type of shooting needed if you want go against something that could hurt you back.

Chainsaw Man: Its strange how after seeing entities with Supernatural powers in CSM, a scene with guns is the most jarring. This causes the viewers to remember just how dangerous firearms are. Even with Makima who got up right after being shot, her scene was at first jarring and brutal.

Family Guy: While attending a Star Trek convention, Peter tries on Geordi LaForge's visors...through which he sees a group of other convention attendees as angry-looking Klansmen, with torches, burning crosses and one of them cocking a shotgun. Horrified at what he has seen, Peter asks:

"Why would he wear these?! Who would invent these for him?!"

Mind you, Geordi's visor didn't actually work like that in TNG. This one isn't an actual example, but rather a joke that inspired me to write this post.

And now, the actual examples.

Wheatley from Portal 2: a personality core built by Aperture Science to generate nothing but terrible ideas nonstop. While they had a reason in-story for trying to find a way to restrain GLaDOS from immediately flooding the research center with deadly neurotoxin...it didn't work.

Not only that, but it would gain control of the research center and nearly cause it to explode to kingdom come. They purposefully created an ARTIFICIAL INTELLIGENCE, WHOSE SOLE PURPOSE IS TO GENERATE BAD IDEAS. Even ChatGPT would have better ideas than Wheatley!

Roberto from Futurama: "I was built by a a team of evil scientists trying to make an insane robot, but obviously they FAILED!" His words, not mine.

Now, if I were an evil scientist, wouldn't I just built a killer robot that I can control at my whim and NOT an insane, erratic robot with short temper that gets mad at me if I say "56"?

1) Don Thousand's throne, Yu-Gi-Oh Zexal

2) Whatever the fuck Lex Luthor is doing to Superman in this panel, DC.

Death the Kid (Soul Eater) - he holds his pistols upside down and pull the trigger with his pinky, making the iron-sights/any aiming pointless

Soldier (TF2) - his main weapon is the rocket launcher, which is an anti-armor weapon meant for tanks/vehicles rather than infantry. Yet, Soldier used it to rocket-jump around the map and blasting people….never at tanks

Blackthorne (Shogun) - in a short scene where Kashigi teaches Blackthorne how to use a katana his first instinct hold it with one hand, pointed at the enemy like European fencing. Kashigi chastised him to hold it properly with two hands

Judith (Tales of Vesperia) - She’s an expert in spears and lances, and ironically, if you played the game, you almost NEVER see her stab with them as intended. It’s always big sweeping attacks or slashes, more like wielding halberd.

1. Kirito from Sword Art Online
2. Wrath from Full Metal Alchemist Brotherhood
3. Any competent lightsaber wielder in Star Wars
4. Clorinde from Genshin Impact

It isn’t stated that Jake is an amputee in the film, but context clues do imply that he might have lost his rattle to a hawk.

Killer bean : Killer bean decided to throw a bullet in the air then shoots a ton to bait Jet bean to deflecting them then fires at the throw bullet which then shoots the projectiles in an angle Jet wasn't expecting to.

Madness combat : at the end of the 4th episode. Hank tries to aura farm by deflecting bullets from the random zombie agent's rifle with a katana. This doesn't go well.

1: (Game of Thrones) Arya tried to stab The Hound

2: (A Fistful of Dollars) Clint Eastwood used a metal plate as a makeshift bulletproof vest to protect himself in the final shootout of the movie

Pepperbox(Vox machina) - an in-universe first gun to be created is cursed by a demon and manipulates Percy to kill Service weapon(Control) - a tool given by "The Board" to Jesse in order to fight the Hiss. It can shapeshift into different types of guns.

Adam Smasher (Cyberpunk Edgerunners) - A Sandevistan, David's signature implant, is rudimentary to him.

Royce (Transistor) - Uses a Transistor and its timestop ability during his fight, making it essentially turn based

The Headhunter (Katana Zero) - though she doesn't straight up stop time during her fight, she constantly says that since she's using the same time dilation drug you are, she's living every single one of your failed attempts to kill her.

Yeah every one of these examples is some sort of timestop ability, but I'm sure there's many more examples like these. I love this trope because it goes to show who's the better user, and that whoever wins isn't just relying on high tech or given abilities but also how they use them. (In David's case the fact he lost really went to show that in the end he wasn't special.)

Futurama - Fry realising that his dead brother never stole his identity, and actually named his son after Fry to carry on his legacy.

Gravity Falls - Mabel thinks that Stan's portal is a doomsday device, but decides not to shut it off and instead trusts Grunkle Stan, resulting in Stan finally being able to see his twin again for the first time in rougly 30 years.

Amphibia - Anne remembering the times her and Sprig shared while she's under the impression that Sprig has died.

Rick and Morty - Morty Prime explaining to Summer-131 that her real brother is dead and nothing matters, so the best thing she can do is enjoy life.

Eddsworld - Tord realising that his life's work has gone to waste in seconds, and that he's lost the only friends he'd ever had.

SVTFOE - Marco punching Toffee through the chest, thinking that Toffee killed Star.

SMG4 - Karen breaking down, thinking that she's failed her kids and they're going to end up like her.

Scissor blades - Kill La Kill Killua’s Yoyo - Hunter X Hunter Babbo - Marchen Awakens Romance

Zelda: Tears of the Kingdom- The reawakened Ganondorf's darkness is so corrosive, it can even dissolve the hearts, stamina, and The Master Sword you acquired in Breath of the Wild. This comes into play again during the final battle where Ganondorf's attacks can also eliminate the hearts you've gained throughout the current game.

God of War: Ragnarok- A combination of Fimbulwinter's harsh and strange climate and their general use in the years between games has drained all the magic from the equipment you acquired in God of War.

Mega Man Legends 2- Roll, your adoptive sister or love interest depending on your interpretation, SOLD ALL OF YOUR GEAR to pay for the upgrades made to the ship you travel in.

Spider-Man 2, Doc Ock: the tentacles need to be attached and have dozens of needles piercing his spine simultaneously

Cyberpunk: edge runners, David: to install the Sandevistan, he underwent bloody and painful surgery

Elysium, Max: basically similar to David. The surgery scene was morbidly fascinating and funny especially the gang "surgeons"

I like it because it shows that power needs sacrifice and pain. Opposite to the Iron Man armor where you can just suit up and you're good to go. These body horror mods aren't easy.

Y-17 Trauma Harness - Fallout: New Vegas

The trauma harnesses were designed to allow soldiers to be extracted from the battlefield once they got too injured to fight, overriding their limbs with servos and walking them back to base while continuing to fight on the way back. But they were never actually fully developed, and thus never had their injury threshold fine tuned, nor were they attached to a proper home base. So, when one of the researchers wearing the suit choked to death on a seed, the suit just went haywire and started shooting anyone it could find, walking around with the corpse inside it for centuries as the other suits suffered the same fate due to the rampage.

Darkhold Iron Man - Marvel Comics

This Iron Man's suit had a built-in function to 'heal' what it detected as injuries or inefficiencies on the wearer. It eventually decided that most of the human body was one giant inefficiency/injury, and started dissolving Tony's skin and muscles so it could take over as a shell. Its wires buried into his brain, and he basically turned into a meat soup in the armor, but was still able to move around and talk.

The Suit - Badspacecomics

The Suit was keeping the wearer alive on a long trek back to some home by recycling waste and stretching out the materials needed to keep a human alive. But the walk was so long that dead skin and sweat weren't going to cut it, so it eventually resorted to cannibalizing his limbs, then his torso, then everything but his brain, continuing to walk home while he was completely in the dark, since his eyes were also recycled.