Poka-Yoke is a concept coming from Japan and means mistake-proof. It could be any mechanism helping users to avoid making mistakes while using an interface or product. The concept it’s focus on prevention, influencing the users’ behavior through the design of the product or interface. Poka-Yoke not only improves the user experience, it also helps improving safety.
I would like to show you some Poka-Yoke examples.
SIM Cards. Thanks to the trimmed corner, a SIM Card can not be put into a cell phone in a wrong way.
SIM Card. Picture by Declan Jewell.
On Search. Poka-Yoke concept is used by Google’s search box and by other search engines to suggest users possible search terms. In the example, I mistyped “Poka-Yoke” so the search box proposes to search for the right term. The problem with this behavior is that these suggestions could influence what users search.
Google search box.
iPhone. Every time a user starts a new note on the Notes application for iPhone, the upper case option is on and ready for the first letter. This is a way to prevent orthographic mistakes.
iPhone Notes application screenshot.
USB Connector. Thanks to its inner shape, an USB connector can not be connected in the wrong way.
USB Connector. Picture by PJstoneson.
…actually, the shape of the connector not only prevents from connecting it upside down but also to connect it in the wrong place.
Different shapes for each connector. Picture by Goodrob13.
Padlocks. Good padlocks do not release the key if it is not totally locked, making sure that the mechanism is totally closed and avoiding mistakes. In this case safety is a big issue.
A padlock. Picture by Greenkozi.