When software works, it's because there were layers of measures to ensure quality. In order to set up and maintain those measures, you need to establish accountability for quality, not for individual changes.
In fact, given that making mistakes is perfectly human, I would argue that insisting on accountability for individual changes is counterproductive. Since I'm a grumpy old fart, I'll illustrate what I mean with a story ;)
At one of the places I've worked, there was this workplace survey they would do twice a year, one of those anonymous surveys where they give you a bunch of statements and have you select options ranging from "strongly disagree" to "strongly agree". One of the questions that has stuck with me was "on my team, it feels safe to make mistakes".
For the first couple of years or so, I didn't really grok the deeper meaning of that question. I simply interpreted it as "my team is forgiving of minor fuck-ups" and didn't think more about it. I'm not sure what made it click, but one day I realized that it's not just about not working under a martinet. It's about minimizing the chances of a mistake causing problems and maximizing the ease of recovery from such problems if they do occur.
Being able to point a finger at me or one of my teammates and say "this is the person that screwed up" is not what makes software work.