What are 3 influential factors that led to the colonists declaring independence?

The reasons that the American colonies broke from Great Britain are made clear in the litany of complaints against King George III in "The Declaration of Independence."
One compelling reason the colonies wanted to separate from Britain is that King George III was working to control the population of the colonies by restricting emigration to the colonies, described as "obstructing the Laws for Naturalization of Foreigners."
The king ordered the colonies' royal governors to prevent the passage of colonial legislation that could prove beneficial to the colonies but not to their sovereign.
Great Britain's government also prevented the American colonies from conducting trade directly with other nations. This greatly reduced economic opportunities for the colonies.
Because the people of the colonies (many of whom did not come from Great Britain) wanted more local governmental control and the ability to grow both in population and economically, along with many other reasons enumerated in "The Declaration of Independence," the war for independence was an inevitability.
http://americainclass.org/sources/makingrevolution/rebellion/text8/decindep.pdf