What happens if there is a problem with the smart contract code? What if the actual contracts are not converted to code due to the inherent complexity of these contracts?
In blockchain, because the information is unchangeable, the contract containing the error cannot be changed, so adding an updated contract to the chain must solve the problem. But the problem is that the history of these problems will remain in the General Staff forever, even if the parties wish to remove it.
In addition, even the smartest contracts are vulnerable to human error. Introducing digital currency called Ether, introduced by startup DAO, it has become very popular as one of the ways to use smart contracts in blockchain systems. However, the hackers stole $ 60 million using a human error in the ether code. In this way, even ether was not immune to human error.
Source : Iran Blockchaink Laboratory