Over the past few breaks, I have gone from no driving at college to lots of driving at home, and I've noticed that driving becomes less and less fun the more I do it. Conversations have led me to suspect that this is a general phenomenon. Objectively, contrast the excitement with which a typical sixteen year old feels when they get their license to the average positive affect working adults feel towards commuting, which is lower than any other daily activity. Here are some attempts to explain this:
1) Less novelty means less fun, as in any other experience. In other words, simple habituation to an initially exciting stimuli is all we need to explain the decrease in fun. This is and should be the default assumption, but I don't think it explains why the effect size is so big for driving in particular. Plus, why has driving become more of a chore over time--from 20% considering it so in 1991 to 28% in 2006? There must be more exotic explanations in addition to this basic one, IMNSHO.
2) The more you drive, the more rules you create about how to drive. Specific rules could include things like, "I won't cut people off for no reason," or, "I will resist the urge to honk unless I am truly justified," or "I won't have leaves my bright lights on all the time." Now, once a driver makes rules, it will naturally piss the rule-maker off when other drivers transgress them, especially because there is no clear avenue for retribution. So, the longer a person drives, the more rules he/she will make, and the more adamant the rule-maker will become about his/her existing rules. So, other drivers will be more likely to transgress a veteran driver's rules, and it will be more annoying for the average veteran driver when this happens. These micro-bouts of anger add up and the experience of driving the whole becomes less fun.
3) The more you drive to a specific location, the more confident you are about how long it takes to get there. More veteran drivers generally leave at the exact time that they need to to reach their destination, as opposed to newbies who must give themselves leeway. So veteran drivers are in more of a "rush," and are more annoyed when they miss a light or when some other driver does something stupid to waste their precious commute seconds. These micro-bouts of annoyance sum and make the net driving experience less fun.
4) The more you drive, the more aware you become of all the bad things that could happen while you are driving. These include the possibility of being ticketed for rolling through a stop sign, being in a car crash, or hitting a pedestrian. These events need not actually occur--merely coming close will cause your probabilistic brain to subconsciously reweigh and increase the odds of the event occurring in the future. Your brain's activity will make you more anxious, even though you may not even be consciously aware of why. More anxiety usually means less fun, so driving will become less fun the more often and the more recently you have been driving.
One take-away from all of this is that memory loss is probably the only reason any of us can stand driving at all. We forget our rules, which makes driving more fun; we forget how long it takes for us to get places, which makes driving more fun; we forget all of the bad things that might happen to us, which makes driving more fun. If this is generalizable to other activities, then that's something to consider as our ability to alter memories with neuroengineering moves from fiction to reality.