The (Bad) Design of Everyday Things (Part 3)

Taps with only one control

Unintuitive controls don’t come much better than the new wave of taps - both shower taps and sink taps. When turning on a tap, you generally want some control over the temperature of the water coming out. You may also want control over the pressure. Too high and you flay your skin off in the shower, or result in an embarrassing wet pants patch.

Traditional hot and cold taps aren’t a good design by any means. Remember those old fashioned showers that had rubber hose connectors that fit over your hot and cold taps? You’d spend ten minutes getting the temperature right, get in, then someone would flush the toilet 4 houses away, and you’d get scalded!

Anyway, there are 2 aspects you need to control, temperature and pressure. So why not give the user two controls? You can still get shower controls with this design, though they seem to be going out of fashion. Once again, sleek ‘simple’ lines have replaced usability, by replacing two dials or levers, with one ‘joystick’. Two unrelated concepts are now controlled by one control.

The amount of time I’ve wasted trying to get my shower to the right temperature and pressure! Is front-back the temperature control? Or is it left-right, or right-left. You have to attack this kind of problem in a methodical way. Force yourself to use only one axis at once - though it may be difficult to tell if you are actually only moving one axis, as the control ‘rod’ may be presented to you at any one of a number of quirky ‘cool’ angles. “Ok, that movement increased pressure…good…. but…ow ow, it also made it hot. I must have accidentally nudged the other axis”.
Eughh. Horrible, horrible design.

Put the usability first, and the design acquires it’s own practical, appreciated beauty.

If you are involved in interactive design in any way - be it shower heads or software, then ‘The Design of Everyday Things’ is a must read. Click the image to buy from Amazon.co.uk.