I would assume you would never be able to get an official reason for not receiving a scholarship. You should understand that when the board meets you will receive a Whole Candidate Score (WCS) just like the SAs do. Each section is given points, they are then tallied, the board knows how many scholarships they can give out and if you make it above the line you get a scholarship below the line and you don't.
Your application could have been great in every aspect, but one or it could have been mediocre in all of the aspects. The only one that really can answer if it was one or the other of these scenarios is you.
ROTC scholarship candidates should understand that your competition is not only the kids who only want ROTC (plan A), but SA candidates who apply for ROTC as plan B. The majority of these candidates have amazing stats, for ex. the avg AFA cadet is in the top 10% of their class, has taken the most rigorous course load available, has an SAT over the 2000 marker or an ACT in the 31 range. They also have multiple EC's, most include athletics, Eagle Scout, NHS, leadership in school, etc. The scholarship committee may know that they are applying to an SA, but will still offer the scholarship because their job is to get the best candidates. They also know statistically that @1400 candidates with noms will not get an apptmt, thus they will go to plan B.
As far as re-applying many students do get the 3 yr scholarship. I do not know about other ROTCs, but for the AF, I know several who did receive the 3 yr. They got it because as a freshman they had a strong resume. They were active in the det, carried at least a 3.2 gpa, had ec's (one is in the marching band at a major university, another was selected as a freshman to intern for a senator) AND they had command support.
You will need that command support because they will write a rec for you. If you elect to apply again as a Freshman, day 1 you tell your det administration of your intentions, don't go to them in October and say oh by the way ROTC scholarship aps are due in 2 weeks can you write me a rec?
Most ROTC commanders are very supportive and will do everything within their power to assist you in the scholarship process.
hwtdad,
At least for AF, the ALO also writes recs for scholarship recipients. My suggestion would be to contact them directly and ask where they saw the deficiency in your childs' application. The ALO/BGO/MALO work very closely with SA applicants and they can easily rack and stack his/her issues against the SA candidate from the lower level. (This goes back to the fact that SA applicants apply ROTC). As I stated earlier it may not be an ACT/SAT issue, it may be the fact that they didn't take a rigorous course load or had no EC's besides working at Target. It could be as simple as the fact that they barely passed the PFA and another kid beat them out because their PFA score was higher.