So far, though, bookmarks are forever. If you insist on user registration, passwords, or other cumbersome impediments to pure hyperlinking, you must reduce navigational overhead as much as possible. Users are unlikely to revisit a site often if they have to pass a Berlin Wall's worth of border guards every time. Use a cookie rather than an explicit log-in sequence to track users unless your site has high security requirements. Usability studies show that users almost never remember their passwords, so they typically write them down anyway.
Loyalty is enhanced if the site becomes more valuable to the user at each visit.
The simplest approach is a frequent-browser points , but it is also possible to make the site itself adapt to the user's needs and preferences over time. After several visits, the site will fit the user's needs so well that the user will be reluctant to move to another site that cannot offer the same service initially. Therefore, users will only establish user profiles on sites that have already gathered their loyalty. Customization works better if the site can gather information about users unobtrusively. As another example of unobtrusive customization, search engines could build up databases of user preferences by tracking which of the search result links a user actually clicked on.