The Axiom of Choice

Posted on February 17, 2005 by psu

I have been fortunate enough to get my hands on an iPod Shuffle. I was mostly seduced by the look of the item, but wasn’t sure how the screenless shuffle- only interface would really work out in practice. Surprisingly, the Shuffle is by far my favorite iPod device for day to day use. In particular, its shuffle play is much more enjoyable in the car than shuffling with the normal iPod. This seems odd, since on the face of it there should be no difference between playing songs at random on a Shuffle and doing the same a normal iPod. However, it turns out that they are different in subtle and important ways, and therein lies the reason I find the Shuffle to be more enjoyable. First, let’s review the major differences between the two players. My 40GB iPod basically can hold everything that I currently have ripped on my current iMac. This is around 13GB of music right now, which works out to about 2500 songs or 8 days worth of music. As I add new material into the iMac, I just transfer all of it to the iPod. So, when I want to be able to pick and choose from everything that I own, the 40GB iPod is the thing to take. I love it on planes and other long trips where I have the time to scroll around in the interface and pick what I want to play. It’s less than ideal in the car however, where interacting with the iPod is annoying and dangerous.

The iPod Shuffle is exactly the opposite. It is not large enough to hold everything I own, and the player has almost no user interface at all. However, iTunes has a system called “Autofill” for randomly downloading songs from a smart playlist into its 1GB of flash memory. The fact that it does this from an iTunes smart playlist is critical because it allows for a valuable level of selective filtering. You can filter the songs by genre, ratings, length and so on, so you avoid the problem of shuffle playing a whole audio book, or movements from a symphony. The autofill mechanism will also weight its choices by your own ratings, so you can make it pick from just your favorites. Once the player is loaded, the interface is simplicity itself. Hit play, hit pause, hit next, adust the volume. That’s it.

On the face of it, you’d think that the iPod would be able to do this. That is, you’d think that the iPod would have a single button that you hit to get a random selection of the good stuff in your library. But you can’t. Shuffling a playlist requires that you do no less than three or four actions at different levels of the iPod user interface. The result is, you never do it. This leaves you with picking something to play, which also requires more thought than I have time for while driving.

Ultimately I think the issue comes down to choice. While the iPod provides a sophisticated interface for choosing what you want to play, that same interface essentially compels you to always choose what you want to play. Even if you have it set up just like the Shuffle, the interface sits there in front of you, beckoning you to fiddle. The Shuffle, by doing away with this interface, leaves you in the comparatively blissful state of being at the mercy of your robot overlords. Since I can’t fiddle with the playlist, I happily allow the machine to do its job. This removes a small but noticeable amount of tension from my life and ultimately is why the Shuffle makes me happier in the car and for most day to day use.

Admittedly this is a subtle psychological bit of sleight of hand that I am playing with myself. But I think the general principle about interfaces that is at play here is that sometimes choice is good and sometimes choice is bad. It is better in general to hit the common case perfectly than to allow (and thus force) the user to tailor the system on her own. Choice provides flexibility, but can lead to extra complexity and confusion that the user does not want. Outside the realm of music players, this is something I learn every time some bad ass punk assasinates me in Halo 2 while I’m standing there trying to choose between the shotgun and the sword.

Oh, the Shuffle is also wicked small.