Bad design or evil plot to prevent caffeine addiction?

Above is a picture of the coffee maker we have at the Stanford Center for Biomedical Research. Can you figure out how to make a large coffee with light strength?

For the first month or two that I was at Stanford I did not know how to re-configure the coffee setting on this machine. I took whatever was the last configuration, so sometimes I got an expresso, sometimes a small coffee, or perhaps a large one, all at varying strengths. It wasn’t until I finally observed someone that actually knew how to use the machine that I figured out how to change the coffee configuration.

So, the answer to my original question, “Can you figure out how to make a large cup of light coffee?” is that you need to press your finger against the lights at the top of the machine to adjust the coffee size and strength. Not only do you need to press down on the light, you need to do it for about a second. Thus, for a large coffee with light strength, you would first hold your finger against the large cup on the left-hand side, once that light switches, then hold your finger against the single coffee bean on the right, indicating light strength. (See picture below, I’ve circled the “buttons” you need to press.)

Is this poor design or am I just an idiot? Or perhaps I should have just asked someone about how to use the coffee machine? Well, first, I couldn’t really ask someone because A) I’m a dude and B) I have a PhD in Computer Science preventing me from ever acknowledging that I don’t understand something technical :-). So that option is out.

As for, am I just an idiot? My argument is of course, no, I am not :-). As further empirical evidence, I also know that I am not the only person that has struggled to use this thing. I was actually getting coffee recently and a guy that has been in the group for several years asked me how I was able to get two cups at once. Therefore, my argument is, it’s a coffee machine for crying out loud, anyone should be able to use it. So, assuming that, what’s wrong with the design?

The big big big issue with using what looks to simply be indicator lights as buttons to re-configure the coffee is that there is really no obvious feedback that the lights are something you can press. Not only that, but you have to press them for a period of time, so just running your finger over them, does not change their state. To toss out a Human Computer Interaction term, these lights have no pressing “affordance”.

An affordance is “an actionable property between the world and an actor“. That simply means that certain objects have physical properties that indicate specific actions. For example, a lever affords pulling or pushing, handles are for holding, wheels are for turning, etc. However, a light isn’t really for pressing. On the coffee machine, the light is flat, there is no physical feedback to indicate that a pressing action or a change in the coffee configuration is about to occur when you place your finger on it.

The sad thing is, this is very easy to address. If the coffee manufacturer simply made the lights beveled or slightly concave like the iPhone’s button and had them actually press in when you pushed your finger against it, I think people would figure it out.

Alas, that’s enough harping on this issue. One of the problems with learning about design is that it’s a tough skill to turn off. You’ll constantly see poor design and be irritated by it. Welcome to my life of torture :-).