Jeff Atwood has a nice blog post on why people make dumb design decisions. It delves into why Fitt’s law works in both its normal and inverse ways. It’s definitely something I am acutely aware of – how do you prevent somebody from doing something easily? Advanced users might like having every single control in the universe at their fingertips, but that sounds like giving one enough rope to hang themselves with. User interfaces need incentive to work well, I think, and you condition the user based on those incentives as well as disincentives. It also makes me acutely aware of all of the flaws in user interfaces on a day to day basis.
Take cars, for instance. I’ve always loathed a lot of car stereos because they cram lots of tiny buttons into a small area. What’s the point? It makes it very difficult to memorize and feel out what’s going on when there’s tons of buttons… let alone being able to read them. How about television remotes? So many of them have bad design, with no feel at all. The worst are the cheap ones – just a bunch of buttons slapped together. No real thought put into people using the remote control.
Some of the most clever designs in preventing people from using things are ideas like the button cover, or the recessed button. Reset buttons on PCs should be smaller and recessed compared to main power buttons, for instance, to reduce accidents. Kaboom switches, say for bombs, should have a cover to keep you from accidentally blowing yourself up. On my telephone the “hang up” button is far away from the line pickup button, and colored in a bright shade of red, too. I’m not sure if I like those paperclip holes for the manual CD tray releases, though. I never seem to have one around when I need it.