I haven't been at facebook in a while, but seeing that chart at the top which shows the goal metric increase and become statistically significantly higher still

I haven't been at facebook in a while, but seeing that chart at the top which shows the goal metric increase and become statistically significantly higher still makes me subconsciously very happy. One thing a lot of people outside the company probably don't realize is that every team at Facebook is different and the culture of experimentation varies greatly from team to team. When I was there, the people who worked on stories ranking were very serious about user satisfaction and thought deeply about whether changes were good for the user even beyond what could be measured via metrics. I worked a tiny bit on notifications experiments at Instagram (wasn't on a team but monitored and changed some ongoing experiments to improve metrics). At the time, I believe the notifications team was less thoughtful about this. I think this has changed in the years since I left though, based on this blog post and what I've seen in the app.