Why do so many websites feel a need to redesign the site every 2-3 years to keep up with the latest design fads? Do old sites regularly break on new devices /

Why do so many websites feel a need to redesign the site every 2-3 years to keep up with the latest design fads? Do old sites regularly break on new devices / browsers? Or is it all a scheme to generate employment for web developers and demand for the increased hardware resources that are provided by ever-advancing technology? I find it hard to buy the claim that users really care that much whether your website uses the latest fads in infinite-scrolling responsive AJAX design as opposed to an old-school server-generated paginated display. As a user I care about content more than presentation, and usually interface "innovations" just end up breaking and making me unhappy. [1] [1] http://xkcd.com/1309/ http://xkcd.com/1309/