User blog:DE-Note/What Determines the Strength of One's Aura?

I've been thinking of how Aura is the manifestation of your soul and how practically Jaune has one of the strongest. But what determines how much Aura you have? If it's the manifestation of your soul, then would it be based on the character's current state of mind? (i.e Depression lowers the strength of your Aura) Or is it passed down from parents? Willpower? What do you think determines the strength of one's Aura? I believe that is is based on someone's willpower and state of mind, because Jaune has quite a bit of willpower and he's a pretty happy dude. What do you guys think about this?