Minor Plot Hole: When Hercules is adopted by the family on Earth, Zeus and his wife watch over him, mourning their loss. During this time, Zeus apparently never mentioned how his son was stuck on Earth, still alive but unable to come home. Either that or Hades was never around during the possible public mourning Zeus must’ve initiated.
It takes eighteen years, conveniently when Hercules is fully grown, for Hades to learn that he didn’t die, and this begs the question if Zeus ever mentioned his son at all during his absence. He clearly trusted Hades and had no idea that he was behind the sinister plan, so why did Hades never find out about it?
Major Plot Hole: If Hades is surrounded by souls of the dead in the Underworld, why didn’t he check to ensure Hercules’ soul came in when Pain and Panic claimed to have killed him? Did he not suspect anything when Hercules was never amongst his collection of deceased people? You had 18 years to check if your plan worked, I assume the God of Death is a busy man but that gives you a respectable timeframe.
Major Plot Hole: In typical Disney villain fashion, Hades has a good opportunity to quickly end Hercules’ life but chooses not to in order for the script to work. Why did he not consult the Fates to kill Hercules with their magical death string when he found out he was mortal but not yet dead? Wouldn’t that have been so much easier?
Super Plot Hole: The Gods of Olympus have the most retarded logic ever. Hercules is unable to return to his godlike status and to Olympus because he is not a ‘true hero’ - he only earns this accolade when he gives his life to save Meg, his true love, from the jaws of death in an epic climax.
But while his fame understandably doesn’t earn him the status of a true hero, shouldn’t the fact that he was willing to give his life to save hundreds of civilians in Thebes, who moments ago disowned and humiliated him, by fighting the Hydra also a similar act of heroism? What about the countless monsters he defeated to protect and save innocent people? What about when he effortlessly defeats the giant Cyclops monster without his godlike strength just to save the town? What about when he freed all the gods at Olympus and lead the fight against Hades, putting an end to his evil plans?
Zeus wants his son to be a true hero, but the act that grants him the status is him saving someone he loves. Surely the previous examples of him saving people altruistically without biased emotional reasons are a bit more heroic? This makes even less sense when you consider Hercules selfishly sold away his superhuman powers, knowing other people would die and Hades would initiate a sinister plot, just to save Meg. How does that come under heroic? Shortsighted maybe – not heroic.
Plot contrivance: Hades inflicts physical pain on Hercules by throwing weights at him - but goes no further. He could easily have turned Hercules’ head into a splattered red mess by dropping a weight on him but chooses not to because acid trips have more narrative coherence than his character.
Plot Contrivance: Hercules apparently never lost his superhuman strength after the deal with Hades, as he is slapped and kicked by the titanically massive Cyclops and suffers no broken bones or internal injuries - and doesn’t, you know, die.
Plot Contrivance: Pain and Panic lure Pegasus into a dark room to be tied up. They clearly had to get the convenient flying horse out of the way to keep Hades’ plan secure, but didn’t think to stun or even kill it. Literally all they do is tie it up with some ropes in an easily accessible room. Why does Hades still trust these two idiots?
Plot contrivance: How on earth did Pain and Panic manage to grab and kidnap Hercules as a baby? Yes, he’s a newborn, but still shown to possess incredible strength by lifting Zeus into the air, crippling Hades’ finger and eventually giving Pain and Panic a savage beating before throwing them into the sky - this is when they took the form of powerful, vicious snakes.
So how did their pathetically comic dragon forms manage to have a scuffle with the baby and carry him off? Had Hercules flailed, any hand or foot to the face would send Pain and Panic halfway across the universe.
Unaddressed Issue: If Hades was able to summon complex magic to secure a deal with Hercules in return for Meg’s safety, couldn’t he have just used similar magic to make this happen without any strings attached? Like, just make Hercules lose his strength without any benefits? It was pretty easy to do it with a deal, so why not without?
Unaddressed Issue: When Hercules is told by his father to seek out Phil, the trainer of heroes, Hercules valiantly mounts his trusty steed Pegasus and zooms off into the sky in an epic crescendo of musical mania, on a bold path to earn his status as a true hero. Except he was never told who Phil is, what he looks like and where he resides. Hercules just raced off without any details from Zeus and somehow managed to find Phil with ease. How did that happen?
Unaddressed Issue: Accessing the Underworld is as easy as completely ignoring it in the script. Hercules manages to effortlessly find the Underworld to confront Hades, which seems strange because although Gods are the only beings able to live on Mount Olympus, anyone can apparently enter the Underworld. And when I say anyone, I don’t mean other strange creatures like the Fates - I mean anyone, even a man who is completely and utterly mortal save for his strength. Did Hercules just keep digging until he stumbled across Hades’ lair or something?