Getting out quicker is always good.

But the main reason, there isn’t much traffic where you are backing in. But backing out sure as hell will have both passing cars and people assume you see them perfectly well. I also have no depth perception so the ass of my car is like a big unknown. So backing into a spot is easy because I can just use the side mirror to line up my position relative to there cars. Only issue is how far back I can go. Now I got a camera back there, and everything is much easier.