Central to the NFT economy is the abstraction of artificial scarcity. Part of the core ethos of blockchain advocates is in the belief that the technology cannot be gamed or manipulated. The medium (of exchange) is the message. But as with other digital files, digital art can be copied infinitely without degradation. This inevitably shapes the market for digital goods, from software to media to art.
Source: Can an NFT Artist Sell Virtually the Same Work More Than Once?