After reading a fact once, why can trying to recall it beat rereading it?

Answer: Retrieval strengthens access

Rereading adds fresh facts — Rereading can add detail if the first pass was too shallow, so it is not useless. But once the fact is already present, the stronger move is often to make the mind reconstruct it without the page. That act exposes missing links and refreshes cues. Extra exposure feels helpful because it is fluent, not because it always builds durable access.

Retrieval strengthens access ✓ — Right. Retrieval practice is not just a check of memory; it can be a learning event. Reviews report large long-term retention gains relative to repeated studying, and Karpicke and Blunt found benefits even for comprehension and inference questions. The quiz is doing work while it looks like it is merely asking.

Testing only measures it — This is the old classroom intuition, and it is incomplete. Tests certainly measure what is known, but memory research shows retrieval can also change what is retained. Feedback helps, yet retrieval practice can work even without immediate correction. That makes a low-stakes quiz more like a tiny exercise than a tiny exam.