Certain skills or abilities are developed at a young age as the brain mature. Poor living conditions and isolation (some examples) in ones youth for too long a duration will/can cause and miss the window of opportunity. You might be able to find other ways to get through that “learning disability”. But, it will never be as good as if you naturally developed it when the opportunity was there. And, yes there are plenty of variables to this. There was a girl back in the late 70’s that was left in the closet for most of the first 17 years of her life. She was not able to and is not able to speak grammatically correct. Probably better now, but will never be as good as you and I. Example: You would say, “I would like a glass of water.” She would say, ” water glass me.”