Better question is why did the Army sign her up?
I believe in the concept of personal responsibility. Every person is responsible for their actions, intentional or not. The media and liberals are constantly trying to push the point that something is not our fault because we were not capable. It's not my fault that I didn't think about retirement, the government should pay for it. Its not my fault that I was speeding, I thought the speed limit was lower. It's not my fault that I killed 2 children in another car, I was drinking. It's not my fault I'm a criminal, I was born poor.
All of its BS. I've seen people do great deeds with little resources and I've seen people fail trivial deeds with all the help they could ever want. The only difference is that one person says: "It's my responsibility to see that this task is accomplished."
Being oxygen depraved and having difficulty reading is a disability. This does not mean that it is an excuse. She took her ASVAB, she talked to the recruiters, answered questions similar to "are there any conditions mental or otherwise that prevent you from doing your job?", and always had the ability to talk to an Army psychologist stating that she had problems performing her duties. She was trained on the laws of the military and on the code of conduct of a soldier. How far does the military have to bend over to help her do her job correctly?