In America the Catholic Church in particular suffers from (an) acute problem; as the descendants of the 19th and early 20th century mass migrations of Catholics from countries like Ireland, Poland and Italy move farther away from their roots, they are also moving away from an inherited sense of Catholic identity.
The ethnic neighborhhoods with their parochial schools and civic associations rooted in and centered on parish churches have been fading away since World War II; increasingly young American Catholics of European origin are emotionally and culturally distant from the church of their ancestors. If it weren't for immigration from majority Catholic countries to our south, the American Catholic Church today would be facing many of the issues of dwindling membership that challenge the mainstream liberal Protestant denominations today...
Throughout the West religious vocations have collapsed since the 1960s; increasingly the Church does not have the boots on the ground to staff the formidable array of institutions it has developed over the generations or to tend the faithful. One result, little discussed but also common among the Protestant clergy in a number of places is a noticeable decline in the quality of the personnel available to fill top Church positions.
With dramatically shrunken numbers of priests, Church authortities have a smaller pool of candidates to appoint to key posts. At a time when the Church desperately needs the best possible leadership, it attracts fewer outstanding people into its rectories and monasteries.