Data Science Foundations: Know your data. Really, really, know it

Know your data, where it comes from, what’s in it, what it means. It all starts from there.

If there is one piece of advice that I consistently give to every data person that’s starting out, whether they are going to be an analyst, scientist, or visualizer, this is it.

This is the hill I spend the majority of my time on even now, to the point of obsession. It is a deeeeeeep but eminently important rabbit hole.

But why?