[dismantlethesun]

For me, NIH is about the idea of already having deep knowledge of the problem domain so a solution is relatively straight forwards. Sure it'll take X time, and there might be some hiccups, but its all about effort and not having to learn anything new.

Joining a pre-existing project is more reasonable when you just can't replicate the basis of the project without learning a lot of new things.

That's the reason why there's a plethora of compile to JS languages, but only a few actual javascript virtual machines.