Believe it or not, even an Olympian can get set aside if they’re only focused on their sport. (How hard is it to at least mentor others or get involved with some foundation’s work?)
The issue with recruits is not that many are qualified academically and in ECs. It’s the coach pull for kids who are not or are borderline.
In the end, there can always be some wild cards. As they build the class and know they’re near their goals, they may decide to give some kid a chance, though he or she isn’t “perfect.” But that’s under adcom control, not some wisdom or formula CC can impart to lesser qualified kids.