Many DeFi protocols offer impressive and often impossible returns in the banking system. These returns, which can be in the double or triple digits, lead many users to believe that DeFi is the realm of easy money. To avoid disappointment or even losing money, it is crucial to understand where these returns come from. It is essential to keep in mind that there is no magical money. The Luna disaster, whose distant origins include the excessive yield of Anchor for stablecoin, should make us aware of this statement and bring us back to reality.