Data processing is a big, messy prospect, for a lot of reasons. First and foremost, you don't necessarily know whether you can trust the data you're using, but even if you can, you still need to know what questions to ask and how to ask them, you need the right tools to process the data, and you need to know how to interpret the results. Very rarely is this a simple Q&A style interaction where you want to know what is the air speed of a laden swallow. For law enforcement, for instance, it's more like "has this person been anywhere suspicious, contacted anyone suspcious, or done anything suspicious recently?" Asking that question requires you to define "suspicious" a lot more carefully and specifically, and draw information from a lot of other sources, stitch them together and examine the results.
Mokalus of Borg
PS - Learning to ask the right questions is half the point of education.
PPS - Figuring out how to find the answers is the other half.