Just because a character appears to strong doesn't mean that they actually are. If you dig a little deeper, you'll find that some characters who seem like powerhouses are actually anything but. Anime characters who are secretly weak can be sources of humor when they're revealed to be far more pitiful than their bragging implied - Nagamitsu Sakonshougen from Samurai Champloo is a great example of this. But these characters can also grow and change over time, owning up to their lack of power and deciding to do something about it, as Terufumi Sugimoto does in Yowamushi Pedal when he finally realizes that he's not a cycling expert.
These characters may not be strong, but they still deserve some appreciation. Which one is your favorite?
King might just be the epitome of the "secretly weak anime characters" trope. He's an S-class hero known as The Strongest Man on Earth, but those accolades don't spring from actual accomplishments. Rather, they come from extreme luck. Every time King faced down a particularly gnarly enemy, Saitama would appear and take care of it, allowing King to take all the credit.
Hilariously, Saitama didn't even realize that he was the one bolstering his coworkers' career, and he was surprised to learn that King was actually just a weak, lucky dude who would rather be at home playing video games than fighting villains.
In order to motivate Goku and Vegeta to get stronger, Beerus tells the story of Monaka, the hero warrior of the planet Wagashi. According to the god of destruction, Monaka was the most powerful opponent he ever faced.
As it turns out, none of that is even remotely true - Monaka is actually just a delivery guy with no fighting prowess whatsoever. But hey, at least he's good at his job.
To be fair to Mr. Satan, he actually is one of the strongest humans around - it's not for nothing that' he's the reigning World Martial Arts Champion. But because he spends so much time bragging about his abilities, his genuine strength ends up looking pretty puny when it's compared to that of Saiyan warriors like Goku.
With his withering gaze, King Fritz appears to be an intimidating ruler, but the King of the Walls is actually a figurehead with no actual power. Rather than making political decisions, Fritz is more concerned about what he's going to have for dinner.
Who holds the real power? That would be Rod Reiss, Historia Reiss' father.