The Lack of Affordance Problem

The thing is, design is always a question of compromise. In order to make something truly simple and minimal, you have to sacrifice some affordances. And in order to make something truly easy to use, you have to sacrifice minimalism (think of children's toys). It's a balancing act. If you get it right, people will love your products. If you tip just a little too much to the wrong side you fall, and you end up with Vista security prompts or Apple Keyboard USB extension nonsense.

JGC uses the example of the DVD-drive and the serial number as problem cases. But I'd argue that only the DVD-drive suffers. The serial number will not be relevant in 99,9% of daily computing for normal people. Non-hackers don't care about serial numbers. If something goes wrong they call Apple support (or do the Google routine). Of course it's a matter of focus. Do you want people to easily find the serial number, then by all means, make it easier to spot. Clearly Apple don't. The drawback is not just aesthetics but continuos reminding people that a serial number is important (which it isn't in normal use).

The DVD-drive, however, could be better. But think of your hard drives or SD-cards. None of my 5 USB hard drives have physical buttons to eject them. I still need to 'eject' it, which means I'll have to drag it to the bin! How's that for an affordance. It's a legacy UI behavior which is hopelessly misconstrued. Putting things in the bin DELETES them - that's the behavior we've taught generations of users. It's even worse than clicking "Start" to turn off your computer on Windows. If you have a HD full of pictures of your loved ones would you risk putting them in the bin if you didn't know any better...? Probably not.

Physical affordances have their place. Especially in a world of touch interfaces a button becomes a powerful switch (think the silent ringer on the iPhone). But they are like Tabasco sauces - add a little and it can make the dish, add a lot and it ruins it. It's a never-ending struggle.

Disk ejects were designed under very different constraints in the old days, though. I just had a fun trip down memory lane to the days when the Mac had 128k of RAM, 400k floppies, and one floppy drive. Copying a floppy involved at least 5 or 6 disk swaps. Moreover, and relevant to this conversation, you could eject a Mac disk without unmounting it. That was because the system software lived on the boot disk, which you had to remove to load up your documents from your personal disk, but if the Mac needed to refer to a file on a currently-not-present disk it would prompt you for the disk by name, and so it was important to leave a ghostly icon of the ejected-but-not-unmounted disk on the desktop to remind users that the Mac hadn't forgotten about that disk and was liable to request it at any time, so for god's sake don't let someone take it out of the building...

99% of the touch targets are obvious.

There have been videos of babies, 5 year olds and autistic kids using an iPad just fine.

As for the 1% of the rest you can just discover them in time. Not everything needs to be in your face, especially if it's a secondary function. And iPad has tons of discoverability, especially how you can't really mess it up whatever you do, just delete an app and reinstall it in the worst case and you're where you left.