It often increases the value in a card/s, especially if the card is in good condition, as it increases how rare your collectible is. card/s increases in value if there is a high demand for an object of which there is not enough to cover market demand.
It protects and preserves the condition / quality it has now.
It is a guarantee that your card/s is real.
It's cool!
You can more easily exhibit and present yours card/s when encapsulated in a PSA holder.
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