Licensing out your OS to anyone that can slam together a box and unloading product via the likes of ZTE and cheap Asian outfits (i.e., the "other" category) is hardly impressive.
Note that Google only counts activations of devices with Google services. They're not counting all the "cheap Asian" Android devices from companies that haven't licensed those pieces from Google.
As for ZTE, they have some of the most popular phones in Europe right now, because they're both usable and affordable.