One really great that led the colonists to victory was George washington!
he led them really well from the camp of valley forge to the battle of Yorktown. He wouldn’t give up and had a lot of faith in his fellow comrades.
But if George Washington is not the answer you’re looking for, I would say the distance between America and Britain. it was hard to replace british soldiers when their homeland was 3000 miles away. Not to mention the travel in boat, some people died on the way.
ps sorry for bad grammar