When I started at Facebook one of things everyone did during orientation was to put up a diff changing the default text of the search bar at the top of the homepage. This was a good way to familiarize people with the end to end flow of making changes. They didn’t say this explicitly but I think it was also intended to give people a “holy shit” moment when you realize that your silly code change is one button press away from 10 figure page views.

The idea was you make the change, take a screenshot of the result on your dev instance, get it stamped by your “mentor” and then abandon it. AFAIK this had been going on for a while before I got there.

Fast forward a few months and I see a sev pop up. “Default text on www.facebook.com search bar says ‘I am a search bar!’”