Web3 projects routinely report hundreds of thousands of testnet wallets, then watch real usage collapse after mainnet launch. Data from Keyrock, DappRadar, and Memento Research shows 84–88% of airdropped tokens lose value within months, driven by Sybil farming and mercenary users with no intention of staying. This piece breaks down why testnet metrics are structurally unreliable and what actual product-market fit signals look like instead.