I just read an excellent declaration of the principals of UX, "Principles of User Interface Design"
Clarity is the first and most important job of any interface. To be effective using an interface you've designed, people must be able to recognize what it is, care about why they would use it, understand what the interface is helping them interact with, predict what will happen when they use it, and then successfully interact with it. While there is room for mystery and delayed gratification in interfaces, there is no room for confusion. Clarity inspires confidence and leads to further use. One hundred clear screens is preferable to a single cluttered one.
It's a good use of ten minutes.