Another way of getting information about potential customers and their needs is to ask them to evaluate existing Web sites. Use your existing Web site or a competitor's Web site to get a feel for what's right and what's wrong. Recruit some representative customers, and observe what they say they want to do on the Web site, what they actually do, and what steps they take to do it. Make note of the kinds of mistakes they make, and pay special attention to what they say they like and don't like. You might also want to have a questionnaire that they can fill out, to learn more about their demographic information and their interests and subjective ratings.

Start your analysis by finding all the people who sent you e-mail about your Web site. Whether they suggested a new feature or criticized a feature that did not make sense, these are the customers who cared enough to make a comment about your site in the first place. If they live close enough, consider asking if you can visit them for an interview, or if they can come to your office to help evaluate the Web site.

But do not rely only on this type of customer. Because they have voluntarily sent a complaint or suggestion, such customers have already been self-selected as having a certain type of personality or level of expertise that may differ from that of the rest of your customers. Make an effort to find a wide range of people who are representative of your overall customer base.

A customer-centered design process involves first knowing who your customers are and keeping them involved throughout the design process. In knowing your customers, you will learn their skills and knowledge (people), what they want to do on your site (tasks), the equipment and software they use (technology), and the larger social and organizational context in which they work, play, and live (social issues).

The potential customers visiting a Web site, the things they want to accomplish, the technologies available to them, and their social and organizational contexts are all highly variable. This is why you need a good understanding of these variables before starting implementation. The methods we have described here may seem too time-consuming if you haven't used them before. Start with one at a time. Run a few informal surveys or interviews of your customers early in the design process for a new project. As you become more comfortable with the process and its benefits, add more, acting also in a focus group.

If you don't know your customers, it is easy to build features that customers consider only marginally useful or even useless. It is also easy to overlook features that customers deem important. And even if the selected features are right, it is just as easy to build them incorrectly, by organizing the information in a confusing manner, using unfamiliar terms, or by having an error-prone navigation scheme that makes the features impossible to find.