What happens to the posts you don’t publish?

This paternalistic view isn’t abstract. Facebook studies this because the more its engineers understand about self-censorship, the more precisely they can fine-tune their system to minimize self-censorship’s prevalence. This goal—designing Facebook to decrease self-censorship—is explicit in the paper.

So Facebook considers your thoughtful discretion about what to post as bad, because it withholds value from Facebook and from other users. Facebook monitors those unposted thoughts to better understand them, in order to build a system that minimizes this deliberate behavior.

via Facebook self-censorship: What happens to the posts you don’t publish?.