This article is outlining when the feature is done (as clarified in the first paragraph), not when the software is done. The difference is the feature is a product problem, rather than an implementation of software problem. The software problem is done when the requirements are properly implemented and bugs are fixed or non-existant.
If the question is if the user is liking it, that's a product problem. It's a different domain than the software implementation.
If the question is if the user is liking it, that's a product problem. It's a different domain than the software implementation.