Amen to those sentiments.
Yes, there are many possibilities. An obstacle in his path could have caused him to step around it at that particular point in time. Don't know if there were eyewitnesses, or if the driver even saw the young man before he hit him. He did stop and try to help him, and called 911. That probably prevented others from hitting him too.
It is one of those things that makes you wish to turn back time, and have the young man, as well as the driver, to be more careful.
I know..that's when the tiny word IF becomes like a log in our eye.