There’s a door on the 10th floor in the Vox Media office I hate so much. You probably know one of these too. But it’s not our fault.

And luckily, Roman Mars of 99% Invisible magically arrived in my cellphone to send me on a cross-country journey to find out the incredible surprises behind this common complaint:

Don Norman started complaining about doors over 25 years ago. Doors shouldn’t need instructions – the shape of them can guide you through just fine. So why do so many doors need instruction manuals right on the side of them?

When most people complain about something, nothing happens. Don Norman is not most people – he’s a psychologist and cognitive scientist. Don Norman thought about, and wrote about his complaints so incredibly thoroughly that he changed the world. 99% Invisible’s Roman Mars helps tell the story.