Customers will go where it's easiest to shop. Your strongest competitive advantage is to make the customer's shopping experience as easy and rewarding as possible. In real situations, online shoppers rarely provide feedback on site usability, but they often opt to purchase from another online store instead. Ease of navigation and simple, basic choices are fundamental. Dr. Nielsen provides the following 13 rules:
If customers can't find it, they can't buy it.
Make customers feel at home on the home page.
Create a smooth path to buying (navigation).
Help customers successfully search (search boxes).
Present good product pages.
Write for the web.
Cross-sell, don't over-promote. ...