Interesting question. Came across this post (from James Taylor) which gives a pretty good answer.
With analytics – executable analytics, business analytics, predictive analytics or any other kind of analytics – begin with the decision in mind. Figure out what it is you are trying to do, which decision you are trying to improve and work into your analytics and data from there. Be driven by your business needs, not by the data you have. You may find that you don’t need to integrate this data source or clean that one to improve the decisions that drive your business. You may find that you don’t even own the data you need and will need to go shopping for it. But if you don’t start with the end in mind, you will never know.