UI "study": a shower

How hard can it be to figure out how to use a shower? As I found out in my recent trip to the United States, it can actually be quite hard :-) This is a small post about the shower I had to use, pictured below, and some suggestions as to how to improve it.

Note that I’m not a UI person by any measure, but I know what I find confusing and I thought it would be a good exercise to think about why it was so hard for me to figure out how to use the shower (I was relatively close to giving up and calling reception, and for a moment I thought there was something wrong with it).

You can see a picture of the shower controls below. As you can see, there are two things you can manipulate: a big handle in the centre, and a small handle below. There is a label “OFF” at the top, a blue “C” (for “cold”) at the left, a red “H” (for “hot”) at the right, and “HI - TUB - LO” and “LO - SHR - HI” at the bottom.

[caption id=”” align=”alignnone” width=”500” caption=”Shower controls from hell”]Shower controls from hell[/caption]

My first attempt was to “use the affordance” of the shape of the big handle and pull it up, towards me. That didn’t work. Then I tried to turn the big handle, but for some reason it only moved counter-clockwise (?). That was alright I guess, because I wanted hot water. So I turned it just a bit, to get hot water, but not very hot. What I got instead was very cold water. That was pretty surprising, but then I thought that it maybe needed a couple of seconds to reach the right temperature, so I waited a bit. The wait was very irritating because the shower head was fixed, so it was quite hard to stay away from the cold water.

I gave up on waiting, and after a while I noticed that the thing that was pointing to the “C” and “H” wasn’t the handle itself, but the mark on the opposite side on the handle, so I was doing the exact opposite of what I wanted. Then I tried to turn it the other way, but it wouldn’t let me. That was very confusing, and meanwhile I was trying to fiddle with the small handle. It was strange because the labels surrounding it seemed to suggest that the small handle controlled the water pressure, but the truth is I didn’t have to turn it to get water, and to stop the water completely I had to put the big handle on the initial position.

After a (frustrating) while I figured that I could go with the big handle from very cold to cold to mild to a bit hot, what I wanted in the first place.

In summary, these are the things I found confusing and I think should be changed:

  1. The big handle should be a simple circular knob, because the only thing you can do with it is turning it.

  2. Having all labels in the same area is very confusing, because it’s not evident which labels belong to which handle. In particular, that the labels for the small handle “break the continuity” of the labels for the big handle suggests that the big handle should be moved both ways, and that it can’t be moved “through” the bottom part.

  3. I find it amazing that you have to go through “very cold” and “cold” to reach “hot”, why not have “mild” as the default position in the centre, control the pressure only with a different handle, and let the user go from mild to “a bit cold” and “cold” or from mild to “a bit hot” and “hot”?

  4. “Water pressure” has a clear, necessary extreme (ie. “no water”) and “temperature” is basically only a gradient: why does the handle with a clear “end position” control the temperature, and the handle with no “end position” control the pressure? Sure, the small handle also controls whether the water comes out of the shower of the bath tub, but surely there are other, better ways to solve that.

Personally, I find the mental model of the other showers I have used much simpler (either two knobs, for cold and hot water; or two knobs, one for pressure and one for temperature). But then again I might be biased because I’ve used them all my life :-)