Rereading feels productive because the material gets easier every pass. That growing sense of ease is the trap: it measures how familiar the page looks, not whether you could produce the answer with the page closed. Retrieval practice, where you attempt to recall something before checking it, consistently produces better long term retention than rereading, and the gap widens the further out the test is. This is the testing effect, and it is one of the more replicated findings in the study of learning.
The reason people reread anyway is friction. Writing good questions about your own notes takes real effort, and it requires knowing what matters, which is exactly what you do not yet know while you are still learning it. Generating questions from the page removes that friction: you go straight to answering, which is the part that actually builds retention.
A workable routine is to photograph the week's notes on Friday, generate ten to fifteen questions, and answer them cold on Monday without looking at the notebook. What you miss on Monday tells you precisely which pages to reread, which turns rereading from a default habit into a targeted one.