As someone who went to Catholic school from kindergarten thru 12th grade, I can think of 2 out of the thousands of my classmates who still practice their faith regularly. Turns out 12 years of a Catholic school is enough to make you lose interest in going to church.
You can imagine that people of all religions have followers whose own personal experiences led them to leave their faith. People are sharing why they left their faith in a viral thread that asked former churchgoers to share what ruined religion for them.