Because you rated it Again. A card you get wrong goes to the back of the current pile and returns before you close the app, rather than waiting until tomorrow.
Getting a card wrong and then not seeing it again for a day would be a strange way to learn it. The whole point of marking something Again is that you did not know it, and the useful response is another attempt while the answer is still fresh.
Hard, Good and Easy all count as correct answers, and all three schedule the card for a future day rather than the current session. They differ in how far out it goes: Hard grows the interval slowly, Good is the normal case, Easy pushes it further than usual.
A card you fail repeatedly is usually a badly written card rather than a hard fact. The common causes are a card carrying more than one idea, a question with several defensible answers, or wording so close to another card that you cannot tell them apart.
Splitting or rewriting the card fixes more repeat failures than any amount of patience does.
The queue is shuffled every session. A fixed order lets you learn the sequence instead of the material, and you find out the difference in an exam where the cues arrive in a different order.
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