What turned the tide of the Seven Years' War (French and Indian War) in favor of Britain?

A change in British leadership and military policies turned the tide in favor of Britain during the Seven Years War. One of the biggest policy changes was the implementation of the "blank check." Authorized by Prime Minster William Pitt, this policy allowed the British military to spend as much money as they wanted on weapons and resources, as long as this resulted in a British victory. This policy works. However it causes massive debt for the British government.