What makes people lose their faith?

I have always considered myself very lucky not to have undergone a crisis of the faith to where I felt like leaving the Church. I suppose it was grace that has kept me in the fold. I always found answers in the Church, and no matter what thing was happening I always thought the sacrifice of the Mass, and the Real Presence was the "bottom line." And Matthew 16 is something I believe in - God not wanting to leave things a chaotic mess.

But why do people leave? Is it because of what someone DID to them, and they see the Church and its people as hypocritical? Or having tepid faith to begin with, they seize on these incidents as an excuse to "not bother?" I've never expected people in the Church to be sinless - it's unrealistic - and I do believe the Church is a hospital for sinners. And I can't deny John 6 - "Where shall we go?"


What becomes of people who see things happen in their childhood and youth when there is a stain....some person did something mean and hypocritical, or were predators...or just plain cynics?

I know the "fallen away" can be recovered. But what is it that impels the "fallen away" to come back. I always feel like I'm walking on eggshells when I come across people who "used to be Catholic." I mean, I always pray for them, but I'm often afraid to probe as to "why?" For the ones who return is it a "Road to Damascus" thing...or a gradual return? I expect it's different for every person, how best to nudge the person gently?