UnMosqued: Why Are Young Muslims Leaving American Mosques? Documentary by Ahmed Eid.

He finds problems that a lot of immigrant churches also face:

Most mosque leadership is above the age of 52 and is disconnected from the realities of what young people growing up in America really face, that there is an extremely high number of walls/barriers in mosques that deter women from attending, a lack of fiscal transparency, and the fact that many communities do not feel a real need for convert programming thus not retaining many converts that often find themselves without a strong support system as they embrace a new religious identity.