I would like to ask which of the sentences or questions above is correct or what could be the best correction? The message that I would like to convey is that to improve a behavior as a result of gaining greater experience or knowledge of something.
The first is grammatically correct. The second has a problem in that the tense of the tag question doesn't match the main sentence. It should be "You never learn, do you?"
Then the only difference is one of tense: The first is past tense. It concerns a matter in the past:
(on discovering a poor man from a slum can't read) "I understand why you can't read. You never learned, did you? You never went to school?"
The second is present tense, and concerns facts that are unchanging:
(Mother, on finding her son is playing games instead of studying) "I tell you everyday that you need to study, but you never learn, do you? You never listen to what anybody tells you."
The second sentence implies criticism.