Why does this watch cost US$815,000?

New York

IMAGINE a wristwatch that costs US$815,000. Imagine a wristwatch that costs US$815,000 and contains no diamonds or precious jewels. Imagine a wristwatch that costs US$815,000, contains no diamonds, but in some alternate universe of watch geekery may even be considered, yes, a bargain.

The watch is question is the Greubel Forsey Quadruple Tourbillon, of which there are four models.