I chose Steve because he spent his time doing something that affects people other than himself. Most people I know have some aversion to changing the status quo. David has impressive accomplishments are of no importance to anyone but himself, so the state of things before and after David's accomplishments are more or less the same.

In other words, I'm impressed with Steve, not because I'm comparing the amount of work and effort they each put forth, but because Steve chooses to spend his time and efforts changing things.