I think one of the subtle benefits to using well-known libraries is that they've already discovered and handled edge cases. Per most of the reading I've done o

I think one of the subtle benefits to using well-known libraries is that they've already discovered and handled edge cases. Per most of the reading I've done on "Why software development time planning is so difficult", the problem lies with bounding uncertainty. We're pretty good at estimating business as usual, but much less so at producing a number when "there are 3 items, each of which has a ~10% chance of adding 10x happy path time" holds. Or even identifying it might hold! That someone has already found a way to thread the minefield, or dealt with any unavoidable mines, is valuable.