A button invites us to push it. A round door knob invites us to pull it. Stairs invite us to climb or descend them. It’s wonderful how most of the objects in the real world seem to have good affordances – cues that tell people what to do with an object. Thumbs up for the designers of all these easy to use everyday objects!
It’s wonderful how most of the objects in the real world seem to have good affordances
However, every now and then we encounter an object whose affordance is incorrect. Look at the faucet below for example: its form kind of invites you to rotate the knob, but no water comes out if you do so. And because of this false affordance, they had to add a help text to show how to open the faucet: by tilting it sideways! Rotating does do something: it changes the temperature of the water. But that doesn’t help much, if you can’t get the water running in the first place.
The concept of affordance came originally from perception psychologist James Gibson in 1979, and the idea was later modified and made more popular by Don Norman in his book “The Design of Everyday Things” from 1988. But of course not everyone has heard of it.
I’m not complaining, though. Actually I have to be grateful to the designers of these kind of objects, too. We the usability people get a kick out of it every time we see one. We get to state universal truths about the object’s usability and how it should have been designed, and even write blog posts about them. Their affordance invites us to criticize ;-).
P.S. I you have more examples of everyday objects with false affordance, I’d love to see them!