Comment by mojzu

I think they mean that it's code they're not having to write/test/maintain themselves because presumably if you pick a good enough library the quality of code/features are better then what one individual or team could do

While there are issues with this approach like the article outlines, personally I believe it to be better then the alternative of countless developers reimplementing the same feature sets over and over because honestly that just seems like a waste of human time and talent