In Round 1, NBA teams favour drafting younger NCAA prospects. I suspect teams see success as a young NCAA prospect may make it easier to translate to the NBA due to the inherent age and experience disadvantage.
These younger NCAA prospects are at an age and experience disadvantage compared to the oldest NCAA peers (~4 years) , which will only be increased in the NBA.
The older NCAA prospects are at an age and experience advantage which will become a disadvantage when in the NBA.
When comparing the NCAA production of draft prospects to previously drafted prospects, the draft age will be considered in the statistical analysis.