For FB... It probably helps keep the team valued internally + helps with retention & recruiting. For PhD trained types, this kind of paper is almost table stakes.
Less obvious... FB has been laying off teams like this despite productivity ROI intuitions, so if I was there, I'd be careful to quantify current + future ROI - I'm sure there are key #'s not being shared.
* To raise your profile and reputation generally
* The specific publish or perish incentives in academia
* Because you really think you’ve done something interesting and novel, and want to share it with the world
Only the middle one is removed when going to industry.
A great example is https://www.uber.com/blog/research/keeping-master-green-at-s...
I think maybe Gitlab Merge Trains predate it, but it was definitely influential.