Humans are continually changing. So any solution built for them needs to be changing as well. This is why you see continuous iteration and refinement in software design. To illustrate, here's several examples of "design is never done" over the years.
Design is never done: the iOS calculator edition
Design is never done: the iOS camera edition
Design is never done: the Apple Website edition
Design is never done: the Tesla OS edition
Design is never done: the eBay Android app edition
Design is never done: the Android home edition
Design is never done: the YouTube Android app edition
Design is never done: the iOS control center edition
Design is never done: the Lyft mobile app edition
