A quote from Ian Bogost in Unit Operations:
"Videogames are thus subject to two equally strong forces opposing their use as tools for social commentary, social change, or other more "revolutionary" matters. On the one hand, the anthropological history of games has set the precedent for their separation from the material world. On the other hand, videogames inherit a mass-market entertainment culture whose primary purpose is the production of low-reflection, high-gloss entertainment.
Even earnest attempts by game critics and developers to overturn this received conception of videogames can be shown to reinforce rather than challenge the status quo. Raph Koster, Sony Online Entertainment Chief Creative Officer and lead designer of popular massively multiplayer online games Ultima Online and Star Wars Galaxies, offered a recent such effort, a unique book of cartoon sketches and semi-aphoristic insights called A Theory of Fun for Game Design. The book's title already implies Koster's adoption of "fun" as a yardstick for games, but, in an attempt fraught with hazard, he tries to recuperate the term for broader purposes than the production of anonymous desire.
In his attempt to preserve "fun" at the center of the experience of games, Koster musters loose principles from cognitive science; fun, he argues, is the sensation of "our brains feeling good." Koster opposes critiques of fun like Postman's, arguing that we "migrate" fun into contexts. In particular, the primary kind of fun that games produce comes from mystery of a task. In their representational form, what I call unit operations Koster calls "abstract models of reality." For Koster, fun is very nearly a pedagogical category, "the feedback the brain gives us when we are absorbing patterns for learning purposes."
[...]
Unfortunately, Koster's reliance on fun as a first principle for games forces him into a corner. On the one hand, he makes a convincing call for games that fulfill goals beyond mere entertainment. This call is especially constructive given Koster's relative celebrity in the game design community. On the other hand, he argues that the effect games produce in their players--all games, and all players--is "fun." This reliance on a single output for games contradicts his earlier, apparently reproachful observation that a singular expressive goal limits the medium. The reliance on fun poses a conceptual problem for Koster, who must retrofit the revolutionary potential of games to mate properly with the concept of fun that serves as his engine. [...] Koster is hard pressed to avoid the rhetoric of fun as the superficial conveyance of capital so often associated with the entertainment industry, the goal that Benjamin foresees and Postman critiques.
[...]
Koster's insistence on grouping meaningful responses of any kind under the rubric of "fun" is simply perverse."
Anyway, that's just how I tend to think of what happens when people believe that everything in a game has to be "fun."