Why were wealthy monarchs more likely to finance overseas explorations?

Often they were looking for gold. As was the case when the Spaniards first explored the New World. Once the English colonized the New World, the "old world siphoned off the natural resources that we had to offer here, especially wood. In Europe they had already descimated most of the trees and were in dire need of building materials other than stone. Also, Parliament loved to tax the colonists, which was a big reason fo our revolution. Remember the slogan, "No taxation without representation?" The colonists were being taxed by England on so many things but we had no representatives in the English Parliament.