Don Norman, former VP of Apple’s Advanced Technology Group, posted a comment on TedBlog about a common failure of Apple designs:

But now let me tell you my pet peeve: the on-off switch of both the regular iPods and the Shuffle. Historically, one thing Apple has always gotten wrong – on all products, big and small — is the power switch (I even wrote a book chapter about this once). The iPod on-off is a mystery to behold, a mystery to explain to others. The Shuffle is even worse. You have to slide a very-difficult-to-slide slider down some unknown amount. It has two settings, but no marking to let you know where you are. Actually, it has markings but they have zero correspondence to the switch setting. You know, this is NOT a tradeoff. Having a little mark on the sliding part and corresponding labeled terms on the fixed case would be trivial to do. Make usage smoother and easier. Cost no money. Bah.

Why is the slider so hard to slide? Their Industrial Designers seem not to have heard of friction — the fingers slip over the nice smooth surface, while the switch remains stationary. Finally when I finally squeeze really hard, the slider does move, but too far, to the wrong position. And those blinking lights. Secret codes that mean who-knows-what. It sometimes takes me 5 minutes to get my Shuffle to start playing, me continually sliding the switch up and down, pushing various buttons, watching lights go on, blink on, flash, turn various colors. All meaningless.

Just the other day I was reviewing racks of servers with bright warning lights. “What does that indicate?” I asked the admin responsible to see if they could decipher the code. Unfortunately, I was told something similar to what Don might have guessed, “no idea, but they seem to come and go.”

All the way from the personal mp3 player to the datacenter, the sole LED has become a cornerstone of messaging and yet no one seems to be very worried about learning how to interpret its meaning. The old-school hex number codes were one thing, but it seems like an amber or green light blinking erratically is almost guaranteed to be ignored.

To be fair, Don could have mentioned that Apple does provide an iPod shuffle reference card to break the codes.

I like the Check battery code: if you do not see a light, there is no charge. Ah, yes, and if your shuffle is wet, it must be raining.