> Most software houses spend so much time focusing on how expensive engineering time is that they neglect user time. Software houses optimize for feature delivery and not user interaction time. Yet if I spent one hour making my app one second faster for my million users, I can save 277 user hour per year. But since user hours are an externality, such optimization never gets done.

This is what people mean about speed being a feature. But "user time" depends on more than the program's performance. UI design is also very important.