When I read your article's title, "Why People Walk Away from the Church," I had the immediate thought; they aren't walking, they are running away.
It's often a slow build-up of issues or events that lead one to leave their chosen house of worship. Sometimes they leave not because of something the church does or says, but because of something they don't do.
When, over time, that tipping point has been reached, people leave their church without haste.
And, when they leave, it's a hard break.
It takes a lot to leave, but once the decision is made it's a rapid exit.