When other addons (like, say, Handynotes: Shadowlands Treasures or SilverDragon) put icons in your minimap, they have to do it in a way that makes them cover up the player-arrow. If you're like me, that means you'll have a terrible time telling what direction you're facing on the minimap whenever you're near anything interesting.
So: this addon replaces the built-in player-arrow with one that's floating above all the other minimap icons. It can also technically change to other arrows or adjust the size of the arrow, but that's less important.