Why were europeans interested in exploration in the fifteenth and sixteenth centuries?

 well as you know in the 1400s the byzantine empire fell in Asia minor and the Turkish ottoman empire was established. turks were barbaric people so any relationship with them was impossible, the trade routes between europe and asia were blocked by them. so the European countries started to search alternative routes to asia. at the time people taught that the world was flat and the round world was a theory! so people started to consider this theory and they started to go around the world to reach asia. colombus was one of those people. he didn't reach asia or the east Indies but he stumbled upon a new continent. so the primary motive for the fifteenth- and sixteenth-century European voyages of exploration and discovery was to gain direct access to the goods of Africa and Asia.