Lug nuts can strip or seize on the stud if you don't properly clean them when installing/removing them.

I always wipe them with a towel and put some anti-seize on them. Remember to only torque them to 80ft/lbs. If you go by just arm strength most people OVERTIGHTEN causing the threads to strip.

In my experience it is never the lug nut manufacturer's fault always the installer/user.

And yes I've had my fair share of sheared lug nuts/studs. Since I change my wheels/tires about 40 times a year when I autocross.