This is a byproduct of the engineering culture being co-opted by the cult of agile. For some domains, the 80% solution is perfectly fine to launch with. For ot

This is a byproduct of the engineering culture being co-opted by the cult of agile. For some domains, the 80% solution is perfectly fine to launch with. For others, it is quite sloppy and you end up with paper cuts in normal use. Problems arise when you, as a consumer of a library, expect a 100% solution and discover it's only an 80% solution. Worse, most libraries do _not_ tell you what design decisions were made.