This is a long due blog post. I wrote it before the series of blog posts on Usable Software Design (first, second and third) but due to a strange series of events (including totally forgetting that I wrote it) is published after them. In a sense, the ideas from this blog post are superseded by the series on Usable Software Design. In many other senses, it contains a ton of background information...
User-Centric Software Design
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