Why would worldly failure cause muslims, who only care about otherworldly rewards, to rethink their religion?
Well, I'm not sure, but I think that although we can't verify the afterlife, we can verify this life, if a religion is supplying a good formula for leading this life, people will buy it.
Conversely, if its failing to get things right in this life in every which way, people will not trust its vision of the afterlife.
Islam fails in this life on most counts-not only science, but women's rights, literacy, life expectancy, wealth creation,slavery,peaceful societies,even strong families if you see the divorce epidemic in the oil rich gulf nations.
So the oppression of women might make many a feminist minded Muslimah quit the faith after failing to reconcile her belief about gender equality with Islam, a scientifically minded Muslim would be turned off by the lack of intellectual advances in Islamic nations, a person who's into cultural supremacy will be turned off when they see Pakistanis watch Indian movies, the Muslim world watch Hollywood, Japanese anime & Disney but no Islamic equivalents etc.
Sure, at first the Muslimah will try her best to reconcile her feminism with Islam, trying to convince herself that the oppression of women is "culture" rather than sanctioned by the Quran & hadiths, the scientifically minded Muslim will try
to brainwash himself into believing that Islam actually created the modern scientific world, but they only fell back due to violent Western imperialism etc, etc-but I think intellectual honesty will make many Muslims re examine their faith & ultimately quit it.