This is what drives me nuts about Superman in both Man of Steel and BvS. It seems he saves the world not because he genuinely wants to because he feels it's the right thing to do, but more like because he can so, meh, why not. At no point does he seem to actually want to be Superman.
Whereas Diana 100% believes that because she has the ability it is her duty to serve and fight for those who cannot. It's inspiring. Superman isn't.
Absolutely loved her characterization.