Because you want to sleep close to your money.
"The answer, we concluded, had everything to do with timing. In the first few decades of the Internet, you had to be physically close to your technology. That technology, the talent that built it, and the ecosystem that maintained it was in Silicon Valley."
C'mon. You didn't need to be close to your technology. PCs and servers and backbones can be installed anywhere.
You wanted to sleep close to your money. But now you're willing to loosen the leash a little if it gives you more bang for the buck.