It's an over-population problem.Muslims have more children than other religious groups and all Muslims are required to indoctrinate :itching: and raise their children in the Islamic faith.:be polite:
On the contrary, the rise of Islam is on account of the enormous birth rates and theocracy, which dictates suppression of nonbelievers and death to blasphemers.
The philosophy winning the most converts (or more accurately, de-converts) is actually Atheism/Agnosticism, for the obvious reasons, as modern science has disproven the "need" for a deity.