There is an antiquated concept that people must put all of the most important information above the fold because users do not scroll on a website.
Adding small scale animations deliver an element of surprise and thoughtfulness to your website. Animations on your website assist in increasing engagement, adding a layer of interactivity to your site, and making your overall website more interesting than simply having a static design.
Before responsive web design existed the easiest way to have a mobile friendly site was to have two separate websites, a desktop site and a mobile site. Primarily the mobile site would live on an m.website.com domain or a /m or /mobile domain. One of the main issues with this having to redirect all of your desktop URLs to your mobile URL. No one likes trying to go to a specific page on your desktop site, only to be redirected to the mobile homepage, having to find your way back to the content you were looking for. Sadly, many search engines still don’t rank mobile sites high enough for mobile users, so people are often guided to full sites instead of the mobile ones, which offer a superior user experience.