A few weeks ago, my washing machine broke. I can’t say for sure what exactly went wrong, all I can say is that if you put your hand in the sink and touched the washer’s exterior, it gave you an electric shock large enough to jump start an Ocean Liner. My electrician said “it shouldn’t be doing that”, and I’d say I’m inclined to agree with him.

Ordering a new kitchen appliance isn’t particularly exciting, but these days it is quite rare. Washing machines, and indeed most modern electronics, have a habit of just… working. This is a far cry from the late1930s, when “washer tech” was in its infancy and was, for want of a better word, rubbish. Asides from catching fire and “walking” *, machines were generally just too unreliable to justify the purchase. So what changed?

A number of things. But the one I’m interested in sharing is the development of Poka-Yoke culture at Matsushita Electric (Panasonic to you and I). In the late 1970s, Shigeo Shingo, Toyota engineer and father of Poka-Yoke, learned of a factory that had achieved a zero-defect month on a production line that involved 23 workers and 30,000 monthly units. Which line I hear you ask? Matsushita’s Washing Machine drainage pipe division. There’s a sentence to get you excited on a Monday morning.

Impressed by their success, Shingo studied their process to see how they had achieved such reliability on such a complicated production line. What he found was series of simple, cheap and easy to implement devices that had transformed the accuracy of their delivery.  Devices such as a fixture that ensures the pipe can only be inserted in the correct orientation or a mechanical stop that ensures the correct number of clamps/fasteners are applied. All this, applied in conjunction with cultural changes, where production line employees were empowered to speak up if they felt something was wrong, rather than keeping quiet out of fear of disturbing the line.

The upshot of this application of Poka-Yoke was as straightforward as the idea itself; they started to make no mistakes. For over six months following Shingo’s study, this humble drainage pipe division maintained their zero-defect record. The Poka-Yoke approach goes a long way to explaining why today, your washing machine gives you clean laundry, instead of a 240-volt rude awakening. The fact that mine did, and that it was surprising enough to make this week’s Poka-Post, just goes to show how far we’ve come. Now if you excuse me, I’ve a load of washing I need to take out the sink.

 *With no suspension, old fashioned electronic washing machines had to be bolted in place to prevent them from walking (shaking themselves) into your living room, and then catching fire.