The classic example of a bad design is the Norman Door, so named after Don Norman, who popularized how awful they are in his book “The Design of Everyday Things”.
Imagine a glass door with hidden hinges, and a chrome bar that extends all the way across the face of the door. This door could possibly be opened in one of four ways - pulling on the right or left, or pushing on the right or left. When you first approach such a door, you have a 25% chance of getting it right.
Now imagine a building that has two sets of these doors (half the malls in America at one time, it seems). You’d have to open one door, walk a few feet, and open the next door to actually enter the building. Your odds of success: 12.5%. Norman used to go to such buildings and just sit and watch as people flailed with these doors, trapped themselves in the area between the two sets, and in general got frustrated as hell.
It’s really very simple: you put the mechanism for opening the door on the side of the door that opens. If you should pull the door open, you put a handle or grab bar on it. If you should push the door open, you put a push plate on the door. No chance of confusion, and these little affordances intuitively guide people to the right action. And yet, doors are still made incorrectly all the time.
I also hate digital up/down buttons instead of knobs. Whoever thought it would be a good idea to make people repeatedly press a button or press-and-hold a button to get the volume they want, rather than just turning a knob until they hear what they want, should be shot.
GE made a dishwasher at one time where some bright boy decided to make the ‘on’ button multi-purpose. Press it once, and the dishwasher starts. Press it again, and it starts in another mode. Press it a third time, and it dumps all the water and goes into shutdown mode. The problem is that to make it work in modes like that, you had to put a time delay on the switch. Added to that was the fact that the dishwasher took some time to prepare to wash, during which there was no apparently movement or sound. So people would press the button, and nothing would happen. So they’d press it again, and the dishwasher would be in a new state, but nothing would immediately happen. In frustration, they’d press it a third time, and the dishwasher would go into dump-and-shutdown mode.
A whole lot of those dishwashers were returned as defective. and many, many extra service calls where made when there was nothing wrong with the dishwasher, because people just couldn’t figure out what the hell it was doing.
Then there are stoves. Every see a stove that looks like this:
0 0
<-- Burners
0 0
---------
@ @ @ @ <-- Switches
Which switch controls which burner? It’s a mystery! You can guess that the right two probably control the right two burners, but which one is the top burner, and which one the bottom? There’s no way to know.
A better design might look like this:
0 0
<-- Burners
0 0
---------
@ @
@ @ <-- Switches
There is no chance of confusion now. More and more stoves are using this kind of layout, but you still see plenty of the older lame ones.