Elegant ideas are so powerful that to know them is to fully understand them. To understand them is to forget what life was like beforehand – their designed simplicity belies their value.

Here’s a simple idea that I appreciate every week – shopping trolley wheels that are self-arresting on an inclined moving walkway:

Here’s how they work – on normal flooring, the metal wheels roll normally. On the moving walkway, however, the metal wheels fall into the tread, resting the trolley on its rubber stops and allowing me to let go of my heavy shopping trolley. It’s effortless, automatic and the arresting function has no moving parts.

It’s so simple it’s obvious. Anyone could have thought of it, right? Wrong. As a sober reminder, here’s moving walkway travesty from Melbourne domestic airport:

As you enter the walkway you see this sign, telling you to release your handle. Then a smaller warning sign with the same info. Then an emergency stop button to arrest both walkways if needed. When you reach the other end, there’s yet another sign & emergency stop. Finally – just moments from disaster – you hear a looped recording telling you to now ignore all the signs and depress the handle before exiting the walkway. I can see it now – crowds piled up at both ends of the walkway for failing to release and depress their handles at the critical moment.

Why? They fixed the wrong problem. They satisficed on their trolley design, burdening users with the responsibility of protecting life and limb by performing a counter-intuitive task. They didn’t push through the complexity to find the simple solution.

Never underestimate the value of elegant ideas, nor those who generate them.