If your build takes up more than half of the grid where you’re fighting an opponent, you’re going to have the upper hand in the fight.
Simply put, piece control means that you occupy the areas of the grid where an opponent might want to build with your own pieces. If your build takes up more than half of the grid where you’re fighting an opponent, you’re going to have the upper hand in the fight. Ask any pro what’s the most important skill required to win fights in Fortnite, and the answer will be “piece control”.