As many as one-third of the colonists at the time of the American Revolution remained loyal to Great Britain. While every loyalist had his or her reasons, let's look at some of the more common motivations.
First off, the colonists were all British citizens and considered themselves to be Englishmen and Englishwomen. A separate American identity did not develop until some time later. As such, loyalists saw a rebellion against England to be morally repugnant and treasonous.
Many loyalists were appalled at the violent actions of the rebels. They saw the tarring and feathering of English officials, the burning of property, and the firing on English soldiers to be barbarous acts that they could not support.
Some saw the Patriot leaders as opportunists who were hoping to profit politically or financially by cutting ties with Great Britain.
Many loyalists had family and business ties to England. The revolution put these relationships in jeopardy. The extensive trade networks protected by the British Empire were indeed good for global commerce.
The Patriots lacked a clear plan for the type of nation they wanted to create after they declared independence. Loyalists did not want to support a cause without a clear plan for the future.
The British had the world's strongest military at the time. To most, it was inconceivable that an untrained ragtag army of colonial farmers could best the military might of the English Crown. Indeed, loyalists would have been aware of the failed 1745 Jacobite rebellion in Scotland and the disastrous results for those that revolted against English rule.
It is also possible that some loyalists saw independence as an inevitability that could be achieved through peaceful means instead of open rebellion.
Additionally, there were many black loyalists. The governor of Virginia had promised freedom to any slave who fought for the British. About 12,000 black loyalists aided the British in the hopes of achieving freedom.