The Hedonic Treadmill, as explained through Training Day (and some Romeo and Juliet, XKCD, and hot showers)

I’m a fan of the movie Training Day overall, but there is a particular scene which I’ve cited time and time again in talks to explain the hedonic treadmill, happiness in general, and a sound psychological method for designing user experiences that keep people both delighted and satisfied.

It always pays to start with a few definitions.  Delight, in a psych sense, is the momentary experience of happiness; satisfaction is its long-term equivalent.  The hedonic treadmill is a way of visualizing adaptation: the tendency to grow used to whatever our current situation is.  The idea is that you have to keep getting more of something to remain equally happy, like needing to keep walking to stay in the same place on a treadmill, because you will grow accustomed to the amount that you have and it will no longer provide the same hedonic benefit.

Personally, I like to think of a shower: it feels hot when you get in, but without changing the temperature at all, it starts to feel colder over time.  So you have to keep turning up the hot water, a little bit at a time, to feel the same warmth.  It is unclear whether that is a better example, but I like showers better than treadmills.
So now, Training Day.  At one point, rookie cop Jake Hoyt is challenged by older cops about his inexperience, and he says he already has the streets figured out.  “It’s all about smiles and cries,” he says.  “You gotta control your smiles and cries, because that’s all you have and nobody can take that away from you.”

Secret of the streets, maybe not, but certainly the secret to a life of long-term satisfaction. Just like there is no better moment than the first one in the shower, there is no better moment than the peak of most of life’s pleasurable experiences: the first bite of chocolate, a particular part of a sunny day.  Because most pleasures come with a cost, whether it is a hot water bill or the calories in the chocolate bar, the maximum happiness/cost ratio is generally the earliest peak.  And that, right there, is controlling your smiles and cries.

If you like something, eating it all the time will actually reduce how much you like it – your brain will release fewer happiness producing chemicals with every repeated instance, unless it is allowed to rest in between bursts.  But the costs remain the same for each burst: you get the same calories from every bite of candy bar, you just don’t get the same rewards.

Thus, if we control what makes us happy, and try to break it up into small bursts that are suitably far apart, we can avoid the need to constantly turn up the heat in the shower.  As Benvolio says in Romeo and Juliet, “Away, begone. The sport is at the best.”  Get out, while you’re still at the peak.  Five two minutes showers is better than one ten minute shower (unless you’re actually trying to get clean).

So product development.  If you constantly bombard your users with positive benefits, particularly the same positive benefits, they no longer act as any kind of motivational reinforcement.  A song on repeat is not a good song.  Good product folks have to build products that allow people to control their moments of happiness, looking for ways to loop together peaks rather than simply make massive, overwhelming experiences that grow stale.  Because the costs stay the same, for you and the user: they have to keep clicking the button, you have to keep serving up the content, and you want to save that for when it matters.

You have to allow your users control over their own happiness, with occasionally serendipity thrown in.  You don’t put Pandora on a party, you throw it on as background music, and when the algorithm is smart, it knows that and performs its lovely background function, while occasionally throwing in songs out of no where that make you stop and dance and sing.  Or maybe just dance, since your coworkers are now giving you strange looks.  It fulfills its basic function, but looks for the places where you have controlled smiles.

Know how your building fits into people’s happiness and try to honor that.  Look for ways to be the first bite of chocolate, periodically.  It is like XKCD – if there was a new one available all the time, I’d get bored.  Your product, whether you like it or not, always occurs in a context.  Figure out what it is and start tuning for not just the moments of happiness but the long-term satisfaction of correctly timed bursts of brain chemicals.  Science…its in there.