How would the average Ethereum speculator know that the contract is flawed? Given the limited success of other, much easier-to-use blockchain technologies I'm s

How would the average Ethereum speculator know that the contract is flawed? Given the limited success of other, much easier-to-use blockchain technologies I'm skeptical that Ethereum can reach critical mass if every participant must learn the Solidity language and conduct a complete code review of any contracts they call. It seems to me that the Ethereum marketplace has to be married to some kind of source of trust, even one as simple as an upvote/downvote system.