If I can recall that trial period, Pistorious seemed to be an extremely self centered person, who lacked any compassion for the dead girl’s family.
I think he shot her through a closed door.
He isn’t the first top level athlete to use and discard women like worn out toys.
He’s a nutcase and loved shooting his guns. I suspect he thought she was sitting on the toilet and when he shot through the door Mr oh so important thought he would hit the wall and scare her. But she was sitting on the ground opposite the door.