What were the factors that made it possible for the ottoman turks to conquer and control their vast empire they forged beginning in the late 13th century?

1. They were devouted Muslims. Rulers were political and religious leaders and that is why people obey to them.
2. At the same time Byzantine Empire was in decline.
3. Millitary was very good organized, discipline and funded. They also recruited millitary from conquered people,  that is why there were so many soldiers.

The fact that farmers were paid for destroying crops.