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
Do they really need it? Does Google really need playful doodles to deliver the value they consistently provide in search results? Does Stripe really need to spend so much energy on the design of its site and SDK’s, which after all, are primarily for the developers that use their API’s? Does Apple really need to sweat the literally thousands of very subtle and often not consciously noticed interactions on its devices? Marty Cagan, Ensuring Excellence On Taste