Take a look at some of these resources to help understand the usability and what is involved in developing a quality web site:
UseIt.com - the ne plus ultra of website usability commentary and information. Jakob Nielsen is the pre-eminent expert in this field and this is what he has to say about it. "Alertbox " isn't gospel, but it's the closest thing we have in Web usability work.
UsableWeb.com - Keith Instone has been developing this meta-list of Web references on usability and related issues since 1994. You can find almost anything here. Especially useful is his section on the business benefits of usability.
AskTog - Funny, concise and easy to understand, Bruce Tognazzini has been the usability guru for companies from Apple to Healtheon. He's now consulting with the Nielsen Norman group, and he has the best explanation of Fitts's Law (one of the few quantitative rules of usability) around.
UIDesign.net - Mostly for professionals, but contains some information useful for those who find themselves needing to know more about usability and human factors issues.
Web Pages That Suck - Both good advice and good entertainment. What more could you want?