The tendency of the Nephites to trust in the arm of flesh is encouraged by their successes. Their hope was in humility, but their success led to an increase in the kind of pride that separated them from the God. For Mormon, this boasting in the arm of flesh is the harbinger of disaster. Perhaps Mormon is remembering the statement of Nephite that those who trust in the arm of flesh are cursed (2 Nephi 28:31).