Netflix tests everything. They're very proud that they A/B test interactions, offerings, pricing, everything. It's almost enough to get you to believe that rigorous testing is the key to success.
Except they didn't test the model of renting DVDs by mail for a monthly fee.
And they didn't test the model of having an innovative corporate culture.
And they didn't test the idea of betting the company on a switch to online delivery.
The three biggest assets of the company weren't tested, because they couldn't be.
Sure, go ahead and test what's testable. But the real victories come when you have the guts to launch the untestable.