Website design is a combination of conceptualization, structure and looks-feel (theme & colors), functionality and navigation rather than just a Graphic Design. It's become highly skilled work. It's necessary that you take care of all the thing mentioned above while design your website as it will be first thing which communicates with your prospect customers.
It should reflect the Ideal & Strength of your company. To realize maximum return on your investment, you'll need to plan for your web site carefully, Design it to take full advantage of the web's unique capabilities, market it effectively and refine it continually. This requires expertise in a variety of areas, many of which are new to your organization.