The British had loads of soldiers. Far more than the American colonists had. This meant the British had more force and manpower.
The Soldiers Didn't Know the Terrain
Unlike the American colonists, the British were trained to fight. This meant they were better at shooting guns and tactics then them. This would help them greatly in battle
No Public Support
Supplies were given by ship to the British soldiers. Supplies included food, weaponry, and other things needed in the battle. The colonists had little supplies.
I'm too old for this...
The terrain was different then the terrain back home. This proved hard for the British to understand where they were going. This led to the colonists being able to get away quicker.
Back home in Britain the public was not in favor of the war. They believed it was a waste of resources and they missed their loved ones. Instead of patriotism like the Americans, Britian felt the opposite.
The distance between England and the colonies made it rough to get there quick. Since the only way was taking a ship through the Atlantic Ocean, supplies were delayed and so were more troops. This caused a lot of turmoil.