The legitimate version is a hosting or hashrate-rental contract with a real operator running real machines. The fraudulent version simply takes deposits and pays early participants with later deposits.
Treat any guaranteed return as a definitive warning sign: real mining revenue depends on difficulty and price, so nobody can promise a fixed yield. If you cannot verify the hardware exists, assume it does not.
This definition is educational and not financial advice. Crypto is volatile and high-risk — always do your own research.
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