This paper revisits the risks of untrustworthiness, and considers some incidents involving computer-based systems that have failed to live up to what had been expected of them. The risks relate to security, reliability, survivability, human safety, and other attributes, and span a variety of applications and critical infrastructures -- such as electric power, telecommunications, transportation, finance, medical care, and elections. The range of causative factors and the diversity of the resulting risks are both enormous. Unfortunately, many of the problems seem to recur far too often. Various lessons therefrom and potential remedies are discussed.