According to Golden Finance, Nubit founder Yu Feng tweeted that many protocols in the current BTCFi ecosystem forge lock positions through offline pre-signed transactions. This method does not really lock Bitcoin on the main network, but gives a "look" Go up and lock it". Users can submit multiple pre-signed transactions with the same UTXO and have multiple protocols count them as TVL, but in reality the Bitcoin is not really locked anywhere at all. This operation resulted in false inflation of TVL and serious trust issues. The founder of Nubit proposed two solutions: one is to actually put the transaction on the chain and lock the funds through the Bitcoin script address; the other is to use a zero-knowledge proof design to make the lock-in transparent and safe and avoid the risk of double spending.