"Fun" and its relationship to games is a topic that has been discussed ad nauseam, and probably by people more educated and eloquent than myself. Even so, I feel I must contribute my own opinion on the matter. Take the following as you will.
As the title of this post states, I believe that aiming for "fun" in the game industry is the wrong way to go. I understand this may seem a strange statement to make. To clarify, then, I think that "fun" is too low of a goal to aim for. I posit, instead, that we aim for "engaging". Before I go any further, however, I should state the definitions I am using for fun and engaging.
Firstly, I am using the word "fun" to describe something as enjoyable or amusing. "Engaging", then, is being used in this case to describe something that holds or attracts one's attention, or something that is engrossing. These definitions are not extremely different from one another, but the difference is important. The difference, in my eyes, is that fun is merely a subset of engaging. Alternatively, a way for a piece to be engaging to someone is for it to be fun.
Most expressive endeavours (books, movies, television, visual arts, etc) dabble in a wide range of subsets of engaging, but games – aside from a few exceptions – seem to focus primarily on fun. A simple example of this would be Tetris, a game that can engage players for hours on end with naught but fun in the form of a puzzle of falling blocks. A not-as-apparent example would be a game like Bioshock which, despite its heavy message, still strives for its gameplay to be fun – dispatching foes is another puzzle to be conquered. Fun is a brilliant subset of engaging, and it is one of the most effective of the subsets, but there are others to choose from. It would be wise to define and exemplify some of the other subsets before moving on, though.
There are many ways to make an expressive endeavour engaging. As previously stated, one of the ways is fun. Another way is to be abstract. Examples of this would be abstract arts, whether they be visual, literary, or otherwise. Some of these pieces would never be classified as fun or beautiful, but they still manage to engage, even if the number of people engaged is not as great (a number of Andy Warhol's works could fall into this category).
Another way to engage is via beauty. Examples of beauty are bounteous and are visible in both nature and the realm of the artificial (from roses to paintings to people). Beauty is not necessarily fun either in some cases (witnessing a sunset is beautiful, but the act probably wouldn't be described as fun, much like the sunset itself), but it engages.
Yet another subset of engaging would be unsettling. I use the term in this case to be an umbrella that spans from concepts of horror to pieces that aren't necessarily frightening in the same sense, but still terrible. When a piece is effectively unsettling, one can become transfixed without necessarily desiring it. An obvious example of this would be a horror movie that gets screams, chills spines, and raises adrenaline. In this case, the unsettling visuals get one's blood flowing. There are however, cases of unsettling visuals that are just as engaging, but do not elicit the same biological highs. These cases are the primal opposites of fun, but are still thoroughly engaging. These are cases where one cannot look away, despite all urges to do so.
Despite the fact that there are more subsets of engaging to speak of, it is these specific unsettling things I wish to discuss the most. This is due to the fact that I think they are really the farthest things from fun one can get, but they are still engaging. A specific example of a piece that uses this unsettling factor is the film version of Requiem for a Dream (some spoilers may follow, be warned). It is a film that examines the lives of a group of addicts, whether they are addicted to physical desires, unattainable ideals, or both. Near the end of the film, there is a scene in which one of them undergoes electroconvulsive therapy due to a deteriorating mental state. This scene is highly unsettling as the viewer has witnessed this person's downfall, and must endure the sight of this person writhing in pain over and over again. This scene is by no means visually appealing or fun to watch. It is essentially visual torture, at least for myself. I have stated many times to those I know that I never want to see that scene again, but when I first saw it, I could not look away. Despite these negative feelings, I do not regard the scene as something that should never be experienced. The film is an excellent warning about going over the edge in more ways than one, and I highly respect that it did not pull any punches in depicting the terror of it. It was entirely engaging and worthwhile, but it was in no way fun.
To some, this idea may seem to be a turn off. This is an understandable viewpoint to have. But in my opinion, the opposite end of the spectrum of engagement is just as important as the end games are most comfortable with. I do not mean to say, however, that no games have ever tried to reach for types of engagement beyond fun. Examples that spring to mind are the Mu Training in Mother 2/Earthbound, the final boss battles of the games in the Mother/Earthbound series, and the Arsenal Gear sequence in Metal Gear Solid 2: Sons of Liberty (things that better people than I have gone into vast detail with). All of these examples use gameplay to express something that is not fun, but it still engages the player. Even more examples exist, of course, but the point I am trying to make is that the ratio of engagement is heavily skewed to fun when it comes to games, and it should not necessarily be so.
In the end, I suppose I am championing the idea of more variety in games. There is room enough for fun games, unsettling games, beautiful games, games that combine subsets, etc. I have heard too many people discuss the "right" way to make games. I posit that there is no "right" way. As long as the player is interested in playing, the game's existence is justified. The player's engagement is all that matters, and there are many more ways to engage than just by fun, as ridiculous as that may sound to some.
Before I end, I know that this will probably stir up a "games as art" debate. I am under the belief that anything can be art (and as such, “art” is a bit of a bogus term), so please do not condense this idea into another "pro-art" or "anti-art" stance. I merely wish for much more variety in the world of video games, and for more experiences that engage in ways other than just fun (especially in the non-indie game scene). Fun is all well and good, but it is most definitely not all there is, nor is it all that there has to be.
End rant. I hope I made sense.