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
So that its destruction cannot begin If you ask, “Why is Thekla’s construction taking such a long time?” the inhabitants continue hoisting sacks, lowering leaded strings, moving long brushes up and down, as they answer, “So that its destruction cannot begin.” Italo Calvino, Invisible Cities Why We Build the Wall making