Too Human (Not) to Fail
Lena Groeger reports in ProPublica:
A coffee grinder that only works when the lid is on. An electrical plug that only fits into an outlet one way. Fire doors that stay unlocked in an emergency.
Lots of everyday objects are designed to prevent errors — saving clumsy and forgetful humans from our own mistakes or protecting us from worst-case scenarios. Sometimes designers make it impossible for us to mess up, other times they build in a backup plan for when we inevitably do. But regardless, the solution is baked right into the design.
This concept has a lot of names: defensive design, foolproof, mistake proof, fail-safe. None is as delightful as the Japanese poka-yoke.
The idea of the poka-yoke (which means literally, “avoiding mistakes”) is to design something in such a way that you couldn’t mess it up even if you tried. For example, most standard USB cables can only be plugged into a computer the correct way. Not to say you would never attempt to plug it in upside down, but if you do, it simply won’t fit. On the other hand, it’s easy to reverse the + and – ends of a battery when you replace them in your TV remote. The remote’s design provides other clues about the correct way to insert the batteries (like icons), but it’s still physically possible to mess it up. Not so with the USB cable. It only fits one way, by design.
Many consumer coffee grinders . . .