Everyone has their own reaction when discovering wrong data. It might start with a double take or maybe an itching feeling that the number should be a higher. However it starts, it usually leads to an investigation to discover what went wrong. While this is a very normal reaction, I offer an alternative. Before turning over every stone in your ETL, ask a few questions to discover if your “wrong” data really is wrong. In this post I explore what wrong means when it comes to data (spoiler alert: it is not black and white). I also offer a few tricks to diagnose which of the buckets of wrong your problem falls into. Yes, this approach may add an extra step or two in your process, but it can also save a day of work trying to fix something that isn’t even broken.