Everyone is saying it’s so backing out is safer, which is true… but for me that’s not the primary reason.

I drive an Isuzu D-Max. It’s a “ute” (truck?) - not one of the obscenely big ones, but it’s bigger than a hatch back or sedan.

In a narrow bay, or narrow approach, you can get lined up in the bay first go if you reverse in because you start with your ass in more or less the right place, and front of the car which is moving left and right to get lined up is not in the narrow bay until you’re more than half way in.

If you drive in front first you often don’t have enough lateral space to get your rear wheels lined up, so you end up parked akimbo first go, so you reverse out to straighten up and come in again.

Additionally, with a rear camera you can see exactly how much room you have so you can use every centimeter. Looking over the nose you can get to within 15cm or so, but you can always use all the space with the camera without any effort.

Reversing might not be easier than front first the first few times, but with a little bit of practice reversing in does take less effort than going front first.