Not sure how much detail you want so in short:
-The British government provided a sense of security to many. Creating a new form of government would be a tall order.
- Some feared losing access to British resources
- Britain was known for their strong naval forces and America was 100% the underdog. It isn't illogical to assume that revolution would be absolutely crushed. America was young, and those on the side of the revolution did not have the professional training British soldiers did.
Most importantly, revolution scared many, and patriots generally did not go about rebelling in what would be deemed a civil way. That did not exactly ease fears, and many preferred the idea of stability under rule.
That's certainly not everything but I hope that helps