How does an NFT become rare?

Could you explain to me how an NFT attains its rarity? I'm particularly curious about the factors that contribute to its scarcity. Is it solely based on the limited supply created by the issuer, or are there other elements that influence its rarity? I've heard rumors that demand and market sentiment also play a role, but I'm not entirely sure how they work together. Could you elaborate on this? Additionally, how does the uniqueness of an NFT factor into its rarity? Is every NFT truly one-of-a-kind, or are there degrees of uniqueness that affect its perceived rarity? I'm eager to gain a deeper understanding of this fascinating aspect of the crypto world.