Why were cortez and pizzaro able to conquer the incas and aztecs fairly easily?

Cortez and Pizarro had a number of advantages over the Incas and the Aztecs:

-the Indigenous people were highly affected by the illnesses that the Europeans brought, so they were weakend

-The Europeans had guns, which the indigenous didn't have and which the indigenous feared

-the Europeans had horses, which the Indigenous didn't.

One of the main reasons why Cortez and Pizzaro were able to conquer the Incas and Aztecs fairly easily is because both had powder weapons and cannons. These were already two massive things which greatly improved the ability of the Europeans to conquer the Native Americans.