Sorry Rock but I also have to disagree. I don't know what bad luck you've had with the scopes you've purchased. But I do not see this as a common problem. I've had variable scopes for over 50 years from various manufacturers, including Nikon, and I have never had this issue.
I always sight in at the highest magnification to reduce any sight in errors. I never noticed any change in POI at different settings. But I do have to admit that I either shot animals when I had the scope set at its lowest setting while hunting. And if a long shot presented itself I would crank the scope up to max. I can't recall ever using a mid-magnification setting. Everything I ever shot was at either the lowest or highest.