Websites exist so that people can find information or perform a task and it's in everybody's interest to make this experience as easy and pleasant as possible. So how to achieve this?
Users want to do things, not work out how to do them. If they are made to struggle with complicated navigation systems, or fail to find information where they expect, they'll lose interest and find a site that makes their life easier.
Getting it right from the user's perspective is the starting point for all web development and design work and should continue to be the most important consideration throughout the course of the project.
Make like a user
Look at what's being built from a user-perspective from initial information gathering and user-task identification through wire-framing, prototyping, visual design, to user-testing and refinement.
Keep it simple, stupid!
Steer clients towards clear, usable and accessible design in every case, it's for their own good! There are any number of fancy gubbins which may distract and dazzle but if a spinning, flashing logo or a randomly arranged menu is going to confuse and, ultimately, frustrate the user it shouldn't be there.
By making the user your starting point and keeping that focus throughout the design process you reap tangible benefits. Quality user-centred websites look and feel good, instill confidence, enhance reputations, reduce development costs and ultimately increase traffic for client and developer.