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
Customers don't know what they want At the end of the presentation someone asked whether he thought they should do some market research to see what customers wanted. "No," he replied, "because customers don't know what they want until we've shown them." Then he pulled out a device that was about the size of a desk diary. "Do you want to see something neat?" When he flipped it open, it turned out to be a mock-up of a computer that could fit in your lap, with a keyboard and a screen hinged together like a notebook. "This is my dream of what we will be making in the mid- to late eighties," he said. They were building a company that would invent the future. Walter Isaacson, Steve Jobs The iMac