Moroni wanted to point out that Ether had prophesied that another group of people would be brought forth and would possess the land if Coriantumr and the Jaredites did not repent. In Ether 11:21, Ether had previously seen in a vision and prophesied that another group would sail across the ocean led by God “after the manner by which he brought their fathers.” This group, of course, was led by Lehi. This would have been important for Moroni to include, as it involved his ancestry and posterity.