that along with the moment where 

Achilles

's captured slave girl puts a blade to his throat in 

Troy

and asks, "are you not afraid to die?"

and Achilles responds, "die today or die forty years from now, what does it matter?"

Because he was born of a goddess his sense of time and human desires is put into perspective. Where a normal person begs to live for another decade so that they can try to earn their honor back or earn more money.

But to achilles money doesn't matter and the only thing is honor. that's why he goes to troy cause he knows his honor awaits there, albeit also his death.