I love this quote from Keita Takahashi, who made Katamari Damacy but has since left games for playground design (my bolding):
When making videogames, I’ve tried to develop them in such a way so they may be enjoyed by anyone. Also, I believe that things other than what’s usually considered the game, such as a settings/options screen, can be a part of play. Gameplay isn’t just inside the game; everything is the game. Everything should be part of the fun. With this approach in mind, a playground wasn’t something for children only—I want to make something they can enjoy together with their parents as well. That skill, or rather, attitude, is definitely there.
-Everything Is the Game
Also this quote from Mary Poppins, which I oddly came across at the bottom of a menu in a hotel restaurant this summer:
In every job that must be done, there is an element of fun. You’ll find the fun, and…snap! (snaps fingers) The job’s a game!