To me, it seems objectively easier to pull into a parking space forward and then back out of the space when you are ready to leave. You don’t have to line up with the lines while driving backwards, and it’s easier to keep from hitting other cars as well. So why back in? To me, the only advantage I can think of is that you can get out quicker, technically.
Edit: I do not need driving instruction, just wondered why. The reasoning.
As an agent of chaos, sometimes I’ll back in to a pull through spot (though really it’s because I’m already beside it intending to back in by the time I see the other spot is also empty and I might as well just keep pulling forward to back in to the spot instead of backing up to be able to turn my nose into the spot).