How did the treatment of neutral settlers in the south hurt british chances for success?

This refers to events that occurred between 1778 and 1780, during the American Revolution.

Some settlers in the South decided to stay neutral, which meant they did not intend to take sides nor go to battle. The British then treated these settlers with hostility, telling the locals that they should support their side or they would hang their leaders and destroy their land. This aggressive stance provoked the Americans who lived in the South mountains, which lead to the formation of a militia and an opposition to the British. A clash at Kings Mountain between the militia and the Loyalist troop resulted in the death or capture of nearly all of the 1,000 British troops. This victory ended up obtaining support from Southern settlers for the Patriots, hindering the British chances of winning.