In summary, you could say that I'm in this field less because of what you could do with a quantum computer, than because of what the possibility of quantum computers already does to our conception of the world. Either practical quantum computers can be built, and the limits of the knowable are not what we thought they are; or they can't be built, and the principles of quantum mechanics themselves need revision; or there's a yet-undreamt method to simulate quantum mechanics efficiently using a conventional computer. All three of these possibilities sound like crackpot speculations, but at least one of them is right!

• Scott Aaronson, in the preface of "Quantum Computing Since Democritus"

Ideally, you put yourself in a scenario where verifying any possibility has a huge payoff.