Why is Holly trying to prove herself?

Holly wants to be in Recon which is a dangerous unit. As a female, she knows that she has a lot to prove. She believes that her commander, Root, is against her being in Recon, so she has much work to do. On top of all of that, the last mission she went on had problems. Because of this past mission, Holly has to prove that she is capable of handling Recon or else Root will follow through with his threat and have her put on traffic patrol and use another female as first Recon.