protectyouplay briefly introduces the characteristics of card sleeves

To properly insert a card into a card sleeve, hold the sleeve open at the top and slide the card in slowly and carefully. Make sure the card is fully inserted and centered within the sleeve. It is also a good idea to avoid touching the front or back of the card while inserting it to prevent smudging or damaging it.

Basically they are AGAINST using perfect fits sleeves as they might nick corners, damage edges and cards are harder to take out of sleeves.

Card sleeves can be reused multiple times, as long as they remain in good condition and are not damaged or excessively worn. However, some people prefer to replace them periodically to ensure maximum protection for their cards.

Even if you are not into collecting expensive gaming cards, but are into card games, you should still consider getting yourself a pack of card sleeves to keep them safe. Otherwise, your cards will damage, and various notorious players can use that as an advantage and know which cards you have in your hands.