Back in the pre-Pointer Events era, everybody used to handle move events by setting mousedown on the element and mousemove/mouseup on the document. This was to handle the edge case when the mouse leaves the element, and events like mousemove/mouseup wouldn’t reach it.

Here's how the logic would look with the old (pre-Pointer Events) approach using mouse events (note where the addEventListener methods are called)

With Pointer Events, the process becomes cleaner. You can capture all pointer events directly on the element itself, without worrying about the mouse leaving the element.

It allows keeping all pointer-related logic confined to the element.