Color blindness
I'm r/g colorblind, and suddenly the indistinguishability of small colored objects makes sense now.<p>Wow. Okay then.<p>I hate multicolor LEDs with a passion. Those little amber or green dots look identical to me, even when you put them side by side. I use a phone app that uses the camera and shows me RGB values at a reticule. I've gone through rack and racks of equipment with that app, looking for things like dead drives and errored-out ports. Back in the 80s, I borrowed the eyes of cow-orkers (with the cow-orker still attached).<p>My wife was a PM on a project once, and asked what I thought of a bit of UI. The designers had replaced a set of small status icons with colored dots (green=ok, red=bad, puce=alerting, etc.). I explained that I could not distinguish them. They didn't believe me; it took that team about five months to come up with a UI that made sense (the same icons, but with colored, duh).