Most colleges that offer early admission programs do it to attract top students. It is a way both to ensure that top students enroll, and to indicate to them that they are, in fact, top students. In the logic of enrollment management, these purposes, and the early admit process itself, make perfect sense.
But in the logic of student success, the students who need early admission most are not top students, who know how to do school, and who are likely to succeed wherever they enroll. Instead, the students who need early admission are regular students--those who are at the median or below academically, and who have little experience with higher education.
The reason is this--the later a moderate or weak student is admitted and enrolls, the less the likelihood that they will be successful. And if admission takes place after registration begins, the likelihood of success drops even more. In short, students with a marginal academic background need more advising, more access to the right classes, and more time to integrate into college.
(And for those focused on revenue, since marginal students receive smaller merit scholarships, admitting and enrolling them early is a way of ensuring decent revenue.)
So if enrollment management has as its purpose student success in addition to prestige, building a class, and revenue, then early admit programs ought to target students who will benefit most from it--not the stars, but the regular students.