Pretend you are an AdCom. How would you look at it? For me, if a person is reapplying with pretty much the same application, I would give it a slight disadvantage to a person applying for the first time with the same credentials. Shows poor judgement, maybe not owing up to his/her weaknesses, not understanding how the application process works. On the other hand, if a person addressed his biggest weaknesses and re-applied, I would look at him as equal to a first-time applicant with the same credentials. I stress that the changes should be significant though. If you are lacking in community service and you add a small part-time community service experience and reapply, it might look insincere and insignificant. If a school sees you are a re-applicant, then they know that you not only missed the cut at their school, but also every other school that you applied to. Therefore, a significant change must occur for them to feel more secure about accepting you.