Why do so many characters start with "humble" heritage or background but then actually have elite ones?

Yu-Gi-Oh, food wars, Yu Yu Hakusho, Attack on Titan, Black Clover, just to name a few older ones to not spoil. But a few recent ones certainly come to mind as well. (I usually don't like it whenever this happens :( ) There's also toooons of anime like MHA (or like almost every Isekai) where a person with humble beginnings gets gifted huge powers.

Are there any anime that do the opposite of this? And maybe some recommendations of ones were people use their own strength to go from the bottom to the top? - like Hajime no Ippo