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.
You can just pull out of the spot and go, no need to change direction etc.
In a tight car park I have almost got stuck once because there wasn’t enough room for me to back out and get my nose out from between the cars on either side to move forward