Game Nexus did a lot of testing on 12VHPWR Failures and found foreign object debris and user error is the most common causes. They concluded that error are actually very rare and they worried that all the fear around it have caused people to keep checking there cables which is increasing risk of something happen because constantly pluging in and unplugging to check for burn increasing risk of something going wrong.
https://www.youtube.com/watch?v=ig2px7ofKhQ&ab_channel=GamersNexus