In anime and in many other forms of storytelling, the good guys tend to win in the end, overcoming a significant challenge or impossible odds and becoming even stronger in body, spirit, or both. That being said, not every fight ends in a win, and as if by an act of fate, there have been fights where heroes have lost badly.
Sometimes, it's because the opponent is far beyond the hero's weight class, sometimes, they were just in the wrong place at the wrong time, and sometimes, the hero brought it on themselves. Whatever the case, there's been plenty of anime fights where the hero was destined to lose.
10 At The Time, Ichigo Was Way Out Of His League When Renji & Byakuya Strolled Up
Bleach
Despite starting out as just a "Substitute Soul Reaper," Ichigo from Bleach has done pretty well for himself. While Ichigo's victories against the Soul Society's worst enemies have been significant, that doesn't mean he's invincible. One of his biggest losses was when Renji and Byakuya first appeared.
By this point, Ichigo had no experience against another Soul Reaper, much less those on the Captain and Lieutenant ranks. While Ichigo was able to hold his own against Renji, Byakuya effortlessly beat Ichigo and broke his Zanpakuto to boot. This defeat would motivate Ichigo to save Rukia and get strong enough to get a rematch with Byakuya.
9 Once Todoroki Got His Head In The Game, It Was Over For Deku
My Hero Academia
My Hero Academia's Sports Festival Arc had some intense matchups between U.A.'s students, one of which was between Deku and Shoto Todoroki. At first, Deku was able to brute force his way through Todoroki's ice, as he refused to use the full power of his quirk out of spite for his father, but Deku would inspire him to go all out.
Deku put up a good fight, but with fire and ice on Todoroki's side, the match ended badly for him. It isn't hard to see why, as Todoroki had more control over his quirk, while Deku couldn't use his properly yet. As soon as Deku spurned him on, the match was as good as over.
8 Subaru Gets Trounced By Julius & His Own Ego
Re:Zero
While some isekai heroes are overpowered, Subaru from Re:Zero is not, a fact he would learn the hard way many times. One of his most humiliating defeats was when he challenged Julius to a duel for the sake of Emilia's honor, to which he was thoroughly trounced.
Considering that Julius is a trained knight while Subaru had little to no experience with a sword, it's not shocking that he got thrashed badly. Subaru's defeat wasn't just a result of a difference in power, but also his own ego, as he felt he needed to pick a fight with Julius in order to be acknowledged. Instead, all he did was prove how insecure he was and why he had no chance of winning.
7 Mumen Rider Had Zero Chance Against Deep Sea King
One-Punch Man
If Mumen Rider's strength was equal to his spirit, he'd be immensely powerful, but it isn't, so that doesn't give One-Punch Man's bike-riding hero much of an edge. Against Deep Sea King, a monster that ripped Genos apart, Mumen Rider had a 0% chance of pulling off a win.
Despite Mumen Rider's lack of powers and low rank, he still put himself in harm's way to protect innocent lives and managed to buy enough time for Saitama to arrive, and that deserves to be appreciated. Still, it didn't stop Deep Sea King from thrashing him around like a rag doll.
6 Even Bojji's Newfound Skills Couldn't Beat Ouken
Ranking Of Kings
Small, physically weak, and deaf, Bojji from Ranking of Kings didn't have the best chance of becoming a force to be reckoned with, but with some training with Despa, Bojji would prove otherwise. However, Bojji's new strength would be ill-prepared against someone like Ouken.
Ouken's immortality and regeneration made it hard for Bojji to leave a decisive blow on him since he would just get back up even after his vitals had been struck. Eventually, Ouken would outlast Bojji's stamina, leaving him in a pretty dire situation. It's no wonder that Despa referred to Ouken as Bojji's "natural enemy."
5 Jiraiya Went Up Against Pain Alone & Paid the Price
Naruto Shippuden
On a mission to gather intel on the Akatsuki, Jiraiya comes face-to-face with the group's supposed leader, Pain, who controlled six bodies at a time, one of which was his former student, Yahiko. Despite being outnumbered and outmatched, Jiraiya couldn't win, but he didn't run, as he needed to confirm his suspicions about Pain.
Jiraiya could've possibly escaped the battle, but he knew that only he could discover Pain's secret, and given the nature of his ties to Pain, he felt he needed to take responsibility. In the end, Jiraiya succeeded, but at the cost of his life, leading to one of Naruto Shippuden's heaviest deaths.
4 Iskandar Unleashed Everything He Had, But It Wasn't Enough Against Gilgamesh
Fate/Zero
Considering the power levels that the servants of the Fate series are working with, it takes a lot to be on the losing side of a battle. Sadly, only the strongest will survive the Holy Grail War. During Fate/Zero, Iskandar and Gilgamesh clashed, and while Iskandar put up a great fight, even bringing an entire army with him thanks to his Noble Phantasm, it just wasn't enough.
With the Sword of Rupture, Gilgamesh decimates Iskandar's entire army in just mere moments and kills him soon after. Considering that Fate/Zero was a prequel to Fate/Stay Night, there was little to no chance that Rider would make it out alive, but it didn't stop some viewers from hoping.
3 Letting Cell Power Up Was Vegeta's Downfall
Dragon Ball Z
If asked to name the most prominent quality of Dragon Ball's Vegeta, most would likely answer with "his pride," which has gotten him into trouble more than a few times. Vegeta's arrogance led to him letting Cell achieve his perfect form, but this blunder ended up spelling "defeat" for the Saiyan Prince during this fight.
While Vegeta could've beaten Cell in his second form, he let Cell absorb Android 18 and even stopped Trunks from interfering, so he could fight him at his best. Perfect Cell ended up being too much for Vegeta to handle, and as a result, Vegeta nearly doomed everyone for his ego.
2 Mihawk Showed Zoro That He Still Has A Long Way To Go
One Piece
Post One Piece's timeskip, the Straw Hat crew's Roronoa Zoro could stand up to some of the pirate world's strongest, including the Warlords of the Sea and even the Emperors, but that strength was the result of intense training. In order to become the strongest swordsman in the world, Zoro knew he would have to fight the current strongest, Dracule Mihawk, who he fought pretty early in the Straw Hats' adventures.
Mihawk was easily able to fight Zoro off with a small knife and broke two of his three swords. Even Zoro knew how out of his league he was and accepted his loss with grace. Zoro's first fight against Mihawk proved that he still had a long way to go to achieve his dream.
1 Ash's First League Loss Became His Most Humbling
Pokémon
Despite starting from the bottom as the trainer from Pallet Town who overslept, Ash Ketchum from Pokémon has achieved great things during his long journey to becoming a Pokémon Master. Still, that success comes off the back of many losses. Ash lost various Pokémon Leagues over the years, but his first-ever League loss was his most humbling.
During Ash's battle with Richie, he sends out his Charizard, who does not listen to him and whose refusal to battle disqualifies Ash. Ash could've prevented this if he had properly trained Charizard, and his Indigo League loss was the result of the luck that got him that far finally running out. This defeat also defined how Ash handled other big losses.