Spaced repetition and rote memory

The shorter the gap between recalls, the more mechanical the recall becomes.

Drill the same flashcard back to back and you get memorization without understanding.

Wait a few days instead. The memory is only partially there, so you have to re-derive the answer, and the understanding gets iterated on each time.

Cramming repetition is like training only your biceps. When you finally go to work your back, the overactive biceps take over and the back is not allowed to develop.