SCROLL FADING 101

Summary from the TLDR Design newsletter

Scroll fade, a new design pattern, is an animation triggered by scrolling: new elements or content fade in or out once the user scrolls down to a certain point on the page. It can cause serious usability issues when misused. Used sparingly at relatively fast speeds, it can draw user attention, improve brand perception, speed up page loading, and divide your content into smaller, digestible nuggets.