Microsoft did a tonne of heavy lifting to make it so. There were boxed in drivers for virtually everything, and customization was absolutely minimal.

And when you bought a MotoQ, it was stock CE.

Android OEMs have to develop their own drivers to get the various components (screen, GPS, WiFi, Bluetooth, 3G radio, accelerometer, etc.) working whereas with WP7, Microsoft will provide all the device drivers. Part of this can be attributed to the fact that Android devices have a much wider range of hardware options, so it's a lot more difficult to have an uniform set of drivers.