Something that most translations miss is that there are two different words for "hero", each with their own meaning.
The first one is "Eiyuu", which is a "chosen one" type of deal. It's what the other two in this story are: someone with "it".
The other word is the more common one, "Yuusha". It's best exemplified by its other translation: "brave". They're the type of hero that rises to the occasion -- one that isn't born, but made. Anyone can be a yuusha.