Why do I go?

Why do I go? Why do I believe that a chief component of my relationship with God is reaching out to people who don't know Him? After all, if He is all knowing and all powerful, what does He need me for anyway?

"Go therefore and make disciples of all the nations, baptizing them in the name of the Father and the Son and the Holy Spirit, teaching them to observe all that I commanded you; and lo, I am with you always, even to the end of the age." - Matthew 28:19-20

The easy answer is, we go because He said "go". There was no part of that passage that is formed like a suggestion. No, it is a command. Go, go to the poor, the hurting, the destitute, the hungry, the sick, the confused. Go, go across the street, across the room, across the hall, across the world. Go. Make. Disciples.

If Christ is our Lord, and He said "go", do we really even have a choice? The question then isn't, why do I go, but rather, why wouldn't I?