I want to talk about two designed items, the choices behind them, and the resulting ease of use: an alarm clock and a recycling can.
I have a Brookstone alarm clock, with a long-life battery so it will always (or, for longer than the rest of it will last) remember the time, like magic (that's the idea). As a user feature, they built into it the time change for daylight savings. Which is nice, since I don't have to ever change the time, it does it automatically, like my phone and my computer. Except I do have to do it, four times a year, since the US Congress changed when we change the time.
The problem is it's hard coded, and not at all flexible, and the information that is hard coded into it (what date the time change happens) did indeed flex, but the device can't. So, zero was better than two (zero changes if the clock changes the time, twice if I change the time). But now it's four, and if zero is better than two then we know four is pretty terrible.
Automatic time change? Good usability decision. Hard wired? Not good.
Granted these are two different areas of design, but they both remind us of the importance of design, and how little things can make a big difference. Also, flexible systems.