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.
I always back into my home space. It’s a gift to Future Me who’s always in a hurry, and who may find herself blocked in by someone’s contractor’s extra-big pickup truck sticking out of their space. Anyway, my Odyssey drives like a boat but has a very good rear camera, with guide lines, much more precise than judging that front bumper.