“Bad usability in the design of aircraft controls can result in what is cheerfully referred to as CFIT: Controlled Flight Into Terrain.

“The usability of your product may not be quite as critical. If you’re lucky, the mistakes you make in usability design will merely cause people to lose limbs, or, heck, even just thumbs. No biggie!”

Read on: Usability in One Easy Step

(You may recognize this article as an extensively rewritten version of beginning of my book UI for Programmers. Indeed, I’m in the process of expanding and revising most of that book, and that’s what you’re reading here.)