Last year I worked at a start-up that had manually created accounts for a few celebrities when they launched, in a gutsy and legally grey bid to improve their p

Last year I worked at a start-up that had manually created accounts for a few celebrities when they launched, in a gutsy and legally grey bid to improve their proposition†. While refactoring the code that handled email opt-out lists I missed a && at the end of a long conditional and failed to notice a second, otherwise unused opt-out system that dealt specifically with these users. It was there to ensure they really, really never got emailed. The result? http://krugman.blogs.nytimes.com/2011/08/11/academia-nuts/ http://krugman.blogs.nytimes.com/2011/08/11/academia-nuts/ What a screw up! These mistakes are almost without fail a healthy mix of individual incompetence and organisational failure. Many things - mostly my paying better attention to functionality I rewrite, but also the company not having multiple undocumented systems for one task, or code review, or automated testing - might have saved the day. [†] They've long been removed.