What factors led to the Spanish conquest of the new world?

well Some came to America to find a shorter distance from Spain to Why_did_Spanish_explorers_come_to_America, such as Christopher Columbus. Others came to find for "Cities of Gold" such as Hernán Cortez & Francisco Pizarro. Others came as a missionary mission to convert Native Americans to Christianity such as Serra Junipero. Most of these explorers would also claim the land they found to be property of the Spanish land