It’s because most people are lazy and don’t bother. I’ve never had a customer come back to torque the wheels.I have worked in the dealership world for almost 40 years, its not a thing to have people come back and retorque the wheels.
When I do my wheels, or family member wheels, I retorque at least 2x…not including a Check after a 10-20min drive following installation.
So 3x retorque just for peace of mind.