If it was on the left in a side hit situation, you and rescue would never be able to reach it, the door would be covering the latch which would be covered by broken glass as well. In the center makes it easier to access in an emergency.

@Barnie2years The emergency responders always have a very sharp knife with them and the glass would be more likely to be from the windshield which could be just about anywhere. A left-sided seatbelt latch would be way more convenient for people putting kids and otherwise incapacitated people in safely.

@azzow2 I agree it's very inconvenient to put in a car seat. I thought the latch was in the center of the car because the seat belts need to be connected at the shoulder level to a very sturdy part of the car and that is naturally the side post. I was trying to remember it about when we had seat only belts whether daylights in the center or on the outside?