There were many factors:

• Devşirme - For every Christian family there was a "blood tax" where children from those families were taken for military service of the empire. One of them was also Scanderbeg. Families of those children could keep their Christian religion as far as they paid this "blood tax" or even just a gold tax to the collectors. The other families who didn't have enough gold to pay and didn't want their child to be taken had to convert in Islam.

• Coverting to Islam that time meant a lot of privileges behind. Only Muslim families could hold guns without paying any gold. There was a gun culture between Albanians were every family should have a gun and when a family didn't have a gun in their house was a sign that the "man of the house" was dead and there was no other male successor to hold his gun. In that case he was buried with his gun. In cases like loosing their gun or not having one, meant no more honor and pride to that family.

• Political, Economical privileges like getting more land or being a (Grand Vizier) prime minister of Sultan. Ottoman Empire had 53 prime ministers with Albanian origin from 1453-1920.

• A notable ruler Muhammad Ali of Egypt (Mehmet Pasha in Albanian) was ruler of Egypt and Sudan also know as the founder of modern Egypt and the Albanian dynasty of Egypt; for around 150 years until Muslim Brotherhood, and the culminating Egyptian Revolution of 1952 where this dynasty died and the Albanian community in Egypt diminished. His reign and his successors led Egypt becoming one of the most developed states outside of Europe that time. The 'Suez Canal' was opened during reign of his grandson.

So, the reasons were just to have more profits that time.

Well, there were once (combined together) millions of Greek, Bulgarian, Serbian and Croatian Muslims but all were expelled or killed.