I'm not sure why, under a 'just' safety culture there is any conflict, whatsoever, between allowing for people to learn from mistakes, and punishing people who have made a mistake.
It's the difference between punishing someone who ND'd a rifle when they've not been provided with any training, and were pushed into a situation they were unfamiliar with, and punishing someone who is up to date with WHT and was using the rifle in an inappropriate manner.