Depends i guess - if you've got a teammate that is plainly and repeatedly careless/incompetent in his doing you're not exactly going to throw your hands up and think "This is fine, the research says it is", right?

Anecdata: colleague of mine at least twice a week reboots production servers during the day, sometimes by themselves, sometimes along with their ESX-hosts...

His response? "Oops."

Does he ever learn from it? Doesn't look like it...

I mean, i'm not exactly working at a hospital or something - i.e. no peoples lives on the line, but try to explain for the n-th time to someone whose last hours work was lost because someone couldn't be bothered to check if he can reboot that server now or not?