Answer: Making a Mistake

A “poka-yoke” is a design concept introduced by Toyota (via Shigeo Shingo) in the 1960s as part of their lean manufacturing process. To streamline production and decrease errors made by workers, process designers for the company began incorporating elements into the devices in Toyota factories and into the design of the cars themselves. These elements decreased the rate of errors by specifically requiring the user to engage their attention with the process by making it difficult or impossible to use a tool or process in error.

The term translates to “mistake-proofing” and is a truncated and adjoined version of two Japanese words, “yokeru” (avoid) and “poka” (mistakes). While originally used in manufacturing, the term can be broadly applied to any mechanism and design choice that is intended to prevent errors. Specialized plugs and ports on medical equipment that prevent medical staff from plugging the wrong hoses into the wrong ports, high voltage devices that can only be powered on if the case is on and securely fastened, and even the parking lockout mechanism in automobiles (which requires you to insert the key and press down the brake to shift out of park), are all examples of poka-yoke systems at work.