I think we see many here pump up their abilities that they could homebrew an excellent implementation of [insert special feature] better than [insert framework/

I think we see many here pump up their abilities that they could homebrew an excellent implementation of [insert special feature] better than [insert framework/library]. Truth is, I don't trust most software engineers to do that without a vetting of some sorts, and open source software provides that. I consider myself pretty good, having done some serious open source work in the frontend world, but if I had to homebrew a framework like React and all of the pieces to make it work (or Angular, even with my intricate knowledge of it), I would not be able to match everything with performance, flexibility, and good API signatures. Most developers are not experienced with thinking about all 3 factors in tandem, and it shows with the code that is written on a typical basis.