I always yell at people who blame themselves for not being able to figure out a technology, whether it be the UI of a program or the physical interface of a device.  People tend to assume stupidity on their own part;  instead, I tell them to blame the designers.  After all, most people would blame the manufacturer if confronted with a car that was hard to use.  Interesting how simple interfaces (a wheel and two peddles) are expected in some areas and not in others.