she was concerned she would hurt her teams chances at a medal and her own physical health (injury)


"Initially the other Team USA members wanted her to continue competing, according to Biles.
"I was like: I think the girls need to do the rest of the competition without me. They were like 'I promise you'll be fine, we watched you warm-up'. But I said 'no, I know I am going to be fine but I can't risk a medal for the team and I need to call it.
"You usually don't hear me say things like that because I usually persevere and push through things, but not to cost the team a medal. So they were like: OK, if Simone says this, we need to take it pretty serious. I had the correct people around me to do that."