A good distraction can turn the tide of a battle. Completely psychological warfare. Also possible lasting effects during the match. Get a player riled up, there’s a chance they’ll remain distracted and play worse on the overall, while being open to more distractions.
I think a lot of people have been on the receiving end of that. Even just getting outplayed can have a negative effect on your morale, and that can really get you off your game if you let it get to you. Add in a little trash talk from the enemy team, you got a recipe for trouble.