There are several times in the book of Ether where Ether asks Coriantumr to repent, and to call his people to repentance. I am sure that never, in any of those moments, did Coriantumr think, "this is it. This is the decision that will lead to millions of my people being killed." Our choices don't work like that. Usually the choices that will determine the big outcomes are made in the small moments. And Coriantumr's decisions in those small moments determined the destiny of millions. The same can be true (on a smaller scale) in our lives. It's what we do in the little moments, that determine the big picture.