Early enough ?

Hi~ what could be the best interpretation of the words "early enough" in this context?

They should experience academic challenge from early on?

OR They should experience enough academic challenge when they are young?

Thanks for your help in advance~!

Gifted children who have glided effortlessly through the lower grades often do not encounter their first academic challenge until middle school. By that time, they have come to believe that being smart means never having to struggle. Not having experienced academic challenge early enough creates a false expectation of what being smart is. This false expectation can produce a sudden bout of anxiety when the work is not easily mastered and internal fear that they might not be as smart as they have been told.