It's easy to see why recognizing a frequent web visitor is important. Each of us appreciates the extra attention that comes from being considered special. We treat close friends and family differently than we treat strangers or people we've just met. It's a natural part of having a relationship. In business, we recognize good customers and treat them differently than strangers or infrequent customers.
Salespeople talk about doing special things for their best customers.
Product managers talk about identifying frequent buyers and rewarding them with a loyalty program. After all, these are the people who make the business a success. Of course, the traditional method of asking for a user ID and password works, but it doesn't have the same positive impact on the relationship as automatically recognizing someone returning to your site. Having a user enter an ID is like not recognizing your sister's voice on the phone when she calls. There are a number of technologies that web developers can use to tailor the look of the home page and recognize each time a visitor returns to your site.