You can't ask customers want they want

... not if your goal is to find a breakthrough. Because your customers have trouble imagining a breakthrough.

You ought to know what their problems are, what they believe, what stories they tell themselves. But it rarely pays to ask your customers to do your design work for you.

So, if you can't ask, you can assert. You can look for clues, you can treat different people differently, and you can make a leap. You can say, "assuming you're the kind of person I made this for, here's what I made."

The risk here is that many times, you'll be wrong.

But if you're not okay with that, you're never going to create a breakthrough.