Don’t make users think! As far as humanly possible, when you look at a web page, it should be self-evident, obvious, and self-explanatory. People should be able to ‘get it’ – what it is and how to use it – without expending too much cognitive effort
Steve Krug
Author of Don't Make Me Think
User experience is the net result of the interaction between a user and a product. It’s not just about usability or aesthetics, it’s about how the entire system interacts with the person and meets their needs. Every piece, no matter how small, should work together to create a seamless and cohesive experience.
Jesse James Garrett
Author of The Elements of User Experience