I would think that born ins just accept the religion they were born into trusting there parents decision and thereby just accepting everything JW`s said ..
Converts like myself as a late teenager, it depended on my upbringing in a Christian nation , who was taught from an early age that the Bible was the word of God , and just accepted it as fact , JW`s came along and the rest was history .Who knows what the outcome would have been if the Mormons had knocked on my door , or the S.D.A.`s in my vulnerable state at that time and explained there interpretation of the Bible.
I could be wrong , but I don`t think the average person would seek out alternative options when first encountering the beliefs of the JW`s. especially if they have a firm conviction in the first place that the Bible is the word of God.
The deeper search only comes after you begin to see , that things don`t add up ,cracks start to appear in your faith , you begin to see the hypocricy and even deceptions about there own history.etc.
smiddy