Designer, implementor, user, writer A Fragment by Donald Knuth dl.acm.org Thus, I came to the conclusion that the designer of a new system must not only be the implementor and the first large-scale user; the designer should also write the first user manual. The separation of any of these four components would have hurt TeX significantly. If I had not participated fully in all these activities, literally hundreds of improvements would never have been made, because I would never have thought of them or perceived why they were important. Eating your own dog food making
All sorts of ways to use the machine Jobs wanted to sell Pixar's computers to a mass market, so he had the Pixar folks open up sales offices—for which he approved the design—in major cities, on the theory that creative people would soon come up with all sorts of ways to use the machine. "My view is that people are creative animals and will figure out clever new ways to use tools that the inventor never imagined." Walter Isaacson, Steve Jobs In ways you didn't anticipateHacking is the opposite of marketingStretching the productThis tactile form of doodling tools