Born-ins are also subject to pressure from parents, a feeling that not following step is disobedient to mom and dad, and too most of their friends are witnesses under the same pressure. So, everyone is doing it, and if you don't, what's wrong with you?
We're only asked to examine "established" doctrine. Look at the questions and answers for baptismal candidates. They usually only cover age appropriate ones. I was never asked about things like prophecy beyond "why can we be certain that this is the end? and why can we be certain that God will soon fulfill his word?" and the answer was, "because he did it in the past and what he says will happen, happens, Isa. 55:11"
For young kids, you can imagine how simplified these questions can get. So, even in preparing for the questions there is no real push to examine your faith, only to learn the anwers to specified questions using specific scriptures.