At least in our place, we do not really expect them to be productive in the usual sense, but they definitely have ample opportunity to give us a feeling of their place on the bell curve.

(as an anecdote: We currently have some 17 year old apprentice which puts some of our seniors to absolute shame, myself included. The amount of motivation, learning hunger, quick thinking and ability to ask the right questions is really astounding, especially given that he essentially just started and has next-to-no education in our area to speak of as of yet)

All interns need handholding but some need 10x more than others. And yeah, they often end up doing another internship or so at a faang.