Agency

Ether 8:26

"Wherefore, I, Moroni, am commanded to write these things that evil may be done away, and that the time may come that Satan may have no power upon the hearts of the children of men, but that they may be persuaded to do good continually, that they may come unto the fountain of all righteousness and be saved."

This is the purpose Moroni writes. It is not selfish in any way, rather it is for everyone who reads this book. He writes so that we can be saved. He writes also so that Satan may no longer have power upon the earth. We can choose who we want to follow. Moroni knows that choosing Satan will lead to everlasting destruction. Choosing the Savior leads to joy! May we choose wisely.