I believe this accures for many reasons and had happen to me personally. I grew up in church by choose but turned from god from a lack of knowledge and understand in what I was taught and because I believe my church to be a little corrupt. These things accure because first lack of true understanding. The contradictions may point out are due to the manner in which the Bible is written. Example after Judia hung him self one disciple saw a rope, one saw him dead on the ground and the other hanging in the tree. This is a sequence of events not a contradiction. We also have to keep in mind that no man is perfect and without sin except Jesus. So the faults we find in churches and leader are human error. The Bible even addressed this to the churches and those people will be judge for those sins with the strong arm of God. Keep in mind Santa wants the leaders and teachers of the church on his side, because they are people building Gods army. These leaders are human and will sin but many will ask for forgiveness and continue to be Christ like. With out full knowledge and understanding of the word of God it becomes easy to find fault and point the finger. However, God wants you to come to Christ by faith and not by fact.