Tom Deierlein is a soldier who was shot in the pelvis on tour in Iraq. Although his doctors said he may never walk again, he dedicated himself to physical therapy, managed to walk, and then even ran a 10-mile race. He explained that he would never give up because persevering against challenges is part of his identity as a soldier. Duckworth uses Deierlein’s remarkable recovery as an example of how people can succeed by making grit part of their identity.