Why did they move the self-driving car operations to Michigan? It would make sense if there was a business, partnership or manufacturing group out there, but they still could have kept R&D in Mountain View.
Self driving cars eventually need to be able to work in places other than deserts and moderate coastal areas. You need "boots on the ground" so to speak; you can't really break new ground remotely, on the problems they need to solve, with any efficiency.