For me as a teenager of the '70s, I wasn't agreeing with my parent's religion but also began doubting the claims about God. The misogyny I saw both in the religion and the Bible started putting me off too. The lack of God fixing problems in the world when he is claimed to be all-powerful and all-loving were contradictory and did not sit well with me..
My mind is very logical. Religion requires you leave logic and reason behind. This is not me. I am just not wired to be religious.