This is a story of a memorable bug I encountered at work. As with every story of that kind, there are a few ways to look at it: it might save you some time if you encounter a similar issue; it surfaces the hidden work - work that is not visible when you only look at the output and artifacts; it demonstrates the benefits of broad knowledge.
From this short assessment, I knew why they were failing. You see, agile project management isn't enough. As a mathematician might say, "It's necessary, but not sufficient." The underlying goal of agile software development is to rapidly deliver high-quality code that meets the users' needs.