Anki 24.10 Beta

How is the quantity in the ‘reviews’ field measured? I’ve noticed that when I click ‘Optimize’ for the same deck, sometimes it shows 0 (zero), and other times it shows the total number of reviews completed. However, this seems to happen randomly. I’m not sure if returning 0 has any practical effect, but I find this alternation a bit strange. Could you explain why this happens?

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