"Smart" contracts have come under fire after the roughly $50M theft from the cryptocurrency-based DAO, which employs the Ethereum blockchain.  Emin Gun Sirer, quoted extensively in CoinJournal, states that "Writing good contracts has always been difficult ... Smart contracts are orders of magnitude more difficult to write, and there will probably be some spectacular failures ahead. The DAO was a wakeup call for improving the science of smart contracts, so we can avoid some of them.  However, he continued, disasters can ultimately aid progress: "Had we backed down after Tacoma Narrows, we would not be able to span many of the bigger valleys with suspension bridges today ... We need to explore the boundaries, and expect occasional failures." 

With respect to the Ethereum Foundation itself, Sirer suggested that it could provide different tiers of scrutiny and allow third parties to vet smart contracts. American Banker credits his point with "[getting] at a key issue of the whole fiasco with the DAO, which is that no one thought this much money was going to be put into an Ethereum smart contract so early in the game".  At the same time, Sirer notes, "Who am I to turn to investors and to tell them not to invest in this potential future technology? Clearly, every individual investor saw a value opportunity, and invested an amount that they could afford into that dream. This is exactly how crowds latch on to good ideas, propel them forward with capital, and how we make technological progress. Trying to stop this is like trying to push back on the Apple II because it's not a 64-bit modern PC."