In this HoneyPot documentary on React there is a nice moment where Lee Byron explains how trying to understand and document the code helped with increasing the quality of it:
There were a couple of problems that I faced right away when trying to understand the code base and build something. Not only was the the set of tools and the mental models really different from what I was used to as a UI engineer. The syntax and the programming concepts involved, just the terminology, was also really different. My takeaway was, you know, okay the whole bid here was that this would be simpler but I can’t help but feel like this is really complicated. Mostly as a desire for me to understand the model but also with a hope that it would kind of end up helping resolve some things, I wanted to build a glossary. Like what are all the things the concepts and then what are all the actions or verbs that are going on here. And so I literally just listed them all out. And then I would go back to Jordan [Walke, original creator of React, ed.], I’d go back to other people working on it, and ask questions like did I get this right? Are these definitions right? And they go yeah okay, no you should really think about it that way, and be like okay, well that’s not how this.. And it would go back and forth and back and forth and I’d be honing these definitions and along the way we’d realize like, oh this concept and that concept are the same, we’re going to name them one thing instead of two things. So unwinding all of this and essentially writing up what ended up being like a reimagining of the component life cycle and therefore sort of the entire front-facing API for React. And I was very happy to see like incredible enthusiasm around that. Jordan was like “ah this is amazing, this really clarifies the ideas”. At that point a handful of other folks had gotten involved with the project too and then I spent sort of the next month or so, sort of piece by piece folding those into place and pretty significantly changing the surface API of React in the process. That was I think the first shift from this being a thing that existed mostly in Jordan’s head, that other people were playing with, to a thing that all of a sudden felt owned by the whole team.