Realize however that the prep=schools are not an athletic training center. There are plenty of students at the prep-schools who aren't involved with athletics at all. But it is true that it's designed for someone who with the exception of a particular academy deficiency; e.g. All "A's" except a "D" in chemistry. Or, 3.95 gpa and a 24 on their ACT. So, other than a specific academic deficiency, they would normally have been EXTREMELY qualified.
Now; how does this pan out for those that are "Over-Qualified" academically. That is definitely a problem in the system. Sort of. Ball Park Estimate: Of the 10,000 that apply; (Prospects); 6500 will be considered eligible; (Applicants); of those, 3500 will be considered competitive; (Candidates). And of those, 1700 will be offered appointments; of which 1300-1400 will accept the appointment. Now; we are concerned for this discussion, the other 1800 who are also competitive but DIDN'T receive an appointment. The problem here is that there are so many reasons why they weren't one of the 1700. Many times it's simply because there weren't enough slots available in their district/state. I.e. A representative can nominate 10 applicants. All 10 could be academically within .5 of a GPA. E.g. 3.85-3.90 between all 10 of them. But only the #1 on the list is somewhat guaranteed an appointment. The other 9 will go into the general pool for the academy to choose from. There's simply no way to get all of them into the academy.
So; where does the prep-school come into play? Well, if there is an individual that EXCELS in Extra Curricular activities; EXCELS in leadership positions; EXCELS in sports; EXCELS in volunteer work; EXCELS in all other areas; however they have a 3.9 gpa and a 24 ACT; or they had a 30 ACT but a 3.5 gpa; the Prep-School could be an option. Now, the student that excelled in ALL AREAS and had a 3.9 gpa and a 32 ACT; and the ONLY WAY they didn't get the guaranteed nomination was because they had a couple of other applicants in their district/state that ALSO walked on water and had a slightly higher everything; that person would basically be getting screwed. They couldn't get an appointment; and they can't get the prep school. And if they try again next year, they will have a MUCH BETTER chance of getting an appointment. But to be honest; the person with the 34 ACT and excels in ALL AREAS and doesn't get an appointment; is a VERY RARE situation.
Most applicants fail to realize that the selection process goes way beyond your GPA and SAT/ACT scores. I know PERSONALLY of an individual with a 4.0gpa and 35 ACT that DID NOT GET ACCEPTED to the air force academy. They easily got accepted to 5 private universities; including Ivy League; and currently is a Junior at Yale. This individual I am speaking of, had very little in sports, leadership, or other extra curricular activities. The academies do not want this type of individual. They want well rounded applicants. A 3.85 gpa with a 29 ACT; who varsity lettered in a sport; was a member of some clubs; was a class officer; went to boy/girl state; has volunteer time; did all IB/AP classes; etc.... will beat out the 4.0gpa 36 ACT student with basic activities EVERY SINGLE TIME!!! Hopefully this explains it. If you are an applicant that has the 3.9-4.0 gpa; a 34 ACT; is a varsity sports athlete; involved with leadership, volunteer, community, etc... activities; CFA, Medically Qualified, and excels in all the other areas; then it is very unlikely that you won't get an appoint. If you honestly did excel in all those areas and had those grades and didn't receive an appointment; it could only mean that others scored Higher with their overall scoring.