Why does cramming feel so effective while producing poor long-term retention?

Massed study spikes retrieval strength (feels mastered) but adds little storage strength — so performance is high now and memory is gone later.

When you study the same material over and over in one sitting, each repetition finds retrieval strength already high, so the effortful-retrieval bonus never kicks in — you keep topping up the volatile strength and barely touch the durable one. The result feels like mastery because in the moment you can recall everything. But retrieval strength decays within hours to days, and with little storage strength underneath, there's nothing to fall back on. The fluency of cramming is a mirage.