Most flashcard tools do one of two things on a second study session: replay the deck in the same order, or shuffle it randomly. Both waste your time in a specific, predictable way — you end up spending equal time on cards you've already mastered and cards you keep getting wrong, instead of concentrating effort where it's actually needed.
How Sanviora's Flashcards decide the order
Your first pass through a new deck goes in the order the cards were generated. Every session after that, the deck looks at your full rating history for each card — not just the most recent rating, the average across every time you've studied it — and puts the weakest-performing cards first. Cards you've never rated at all lead the pack, ahead of cards you've rated poorly, which come ahead of cards you've consistently nailed.
Why this matters more than it sounds like it should
Study time is limited, and attention fades as a session goes on — most people study their sharpest in the first few minutes and start rushing by the end. If a deck is ordered randomly or sequentially, your best attention is spread evenly across cards you already know and cards you don't, purely by chance. Weakest-first review deliberately puts your fresh attention where the actual gap is, and your fading attention on the cards you'd probably get right anyway.
The rating scale feeds directly into this
This only works because ratings aren't a simple right/wrong toggle. The 5-point scale — Blank, Hard, Shaky, Good, Instant — gives the reordering something real to work with. A card you rate "Shaky" repeatedly stays near the front of future sessions even if you technically got the answer right each time, because "technically right but hesitant" is exactly the kind of answer that falls apart under real interview pressure.
What changing your mind does
Ratings aren't locked in once you give them — if you restudy a card and your understanding has genuinely changed, rating it again updates that card's standing rather than being ignored or averaged away into meaninglessness. This is deliberate: the whole point of tracking history per attempt is that your knowledge is expected to change over time, and the ordering should reflect where you actually are now, not where you started.
The practical upshot
You don't have to manage any of this yourself — no manually re-sorting a deck, no guessing which cards need more attention. Study a deck honestly, rate it honestly, and by the third or fourth session the deck has effectively built you a personalised drill of exactly the concepts you haven't nailed down yet.