I think it's a senior developer mistake. Even at midsized company developers should not have a direct access to production environment.

At my first job I was tasked to create a newsletter (for customers who had subscribed to it).
My boss told me when I'm done and he looked it over, I can send it out myself.
Used the wrong recipient list and sent it to literally every single e-mail address the company had on file.

When thousands of delivery failure notices, confused replies and angry demands to unsubscribe rolled in, my boss told all my colleagues to step outside the office, and then yelled at me for several minutes straight about how I jeopardized his business by trying to be a smartass and I should run everything by him first from now on. Then he called everyone back into the office and, in front of all of them, praised my initiative, work ethic, and go-getter attitude.

All in all, it was a pretty useful mistake. We could update our contact list, actually received lots of interest in the newsletter from people who hadn't subscribed, and I learnt that my boss is a psycho and could start planning my exit.

Rite