Braden Kowitz writing for Wired:
It’s common to think of data and instincts as being opposing forces in design decisions. In reality, there’s a blurry line between the two. After all, instincts are built by observing the world around us, and those observations are just another stream of data. Statistics help us summarize and understand the hard data we collect, and instincts do the same for all the messy real-world experiences we observe. And that’s why the best products — the ones that people want to use, love to use — are built with a bit of both.
So much yes. It's so easy to get caught up in the power of data and forget about the importance of instincts honed by experience. Braden's approach for when to rely on data or on instinct is incredibly useful, especially to someone like me who isn't a designer by trade, but ends up being involved in (and leading in some instances) design based decisions.
The other crucial element that Braden touches on is research. If you haven't read Just Enough Research by Erika Hall, you should. Research isn't a big scary, academic beast – it's something that everyone trying to make a decision should do. Even one or two sessions of watching someone use your design in real life will have a profound impact on the decision tree going forward.
Erika's book is an extraordinarily practical approach to doing enough research to make a strong decision but no more.