Well,
When I interviewed, the feeling I got was that they wanted to find one non-statistical, compelling reason from you why you were a good fit for Osteopathic medicine. It could have been that you believe in the holistic approach, that you believe in OMM, that you had a great experience with a DO and believe in its principles or that you've always known you wanted to be a doctor.
I think what they really were looking for is why will you be a great doctor, an asset to the profession, your patients and the reputation of DO's. If you could give them that without starting with, "I would be a great DO because...," then you were fine.
For anyone who has not yet interviewed (although this may be the wrong thread for this), consider this in your answers. And take charge a little. That's what I did. They asked a shorter answer question that was not what I wanted to talk about, I briefly, but completely answered the question and then used my time with the mic to convey about myself what I thought would be important to them. And I had to because my stats flat out suck. I've got a lot more in my head than I've been able to put down on paper and letting them know that is everything.
And make the decision to be relaxed, win or lose. Because we also have practicals now, it's even more important to enroll students who don't crack under pressure verbally. Be lightly charming and have an opinion, a cause, a pet-peeve or something that you want to address. You don't have to use it in the interview, but have it in your back pocket. They want to know the problems out there that you want to fix.
This isn't the end-all in interview advice, but I think it's relevant and can help overcome statistical deficiencies. They want a little passion for the industry. They want to meet the spirit and attitude of a competent physician right now. And they just want to provide the info and training. When I was in there I talked about the effects of emotional distress on the immune system and the importance of the old-school doctors in a community that really knew their patients and offered some measure of assistance in all of those areas. We had a cool discussion and it ate up time that I'm sure they would have used to grill me on trivia about the Osteopathic profession or would have asked me why my grades indicate that I'm mildly ******ed.