Two factors: 1. Natural ability and 2. Motivation to put in work specifically for the test.
I’m sorry, but a 3.0 at BYU is just not respected at professional schools, especially on the east coast. And honestly, the church’s hardline stance on gay marriage is making BYU less desirable all over the country. There are A LOT of LGBT people in the medical community, especially at academic institutions. I tried to downplay my association with BYU. Didn’t feel like it helped much at all.
A good friend of mine got into Yale from Idaho state. He had a 3.9 GPA and crushed the MCAT. For Med school, All you need is a solid GPA and a great MCAT score, that is it. That can be achieved anywhere.