Ask HN: How to roll out an internal UI component library

I will be taking on a project to build an internal UI component library at a company with around 100 developers. This is by no means the first time that the company has attempted to move teams to a common library. All previous attempts have failed and to me it looks mostly like challenges with communication, processes, priorities, etc.

I'm interested in hearing about experiences (good and bad) with all the above. How do you roll out a component library successfully? How do you get teams to use it? How do you get people excited instead of being a forced rewrite for them? When do you start getting teams on board? How do you set up processes for feedback?