Saman, why should someone need to understand the user experience to build a user interface? The answer seems obvious to me. The two things are intimately connected. Ultimately, the user experience is delivered through the user interface. An aesthetically pleasing UI is useless if it does not make the features and functionality of the product easy to understand and use.

People who think that specializing in one small part of technology is a good idea, without understanding the context within which it operates, are naive and are cheating themselves and their customers.

No one is cheating me, only themselves. Saman, how long have you been building software?