In retrospect it was a poor assumption on Google's part to think that these manufacturers were actually going to support their customers. That is why they have spend the last 2+ years re-architecting the system to shove a bunch of functionality into things that Google can update or libraries that developers can incorporate into their apps. I imagine when they started out, they did not intend to have a huge amount of the system in a support library that is packaged inside every single app. I bet they also didn't intend to have the bulk of new features be in the Google Play Services package. Yet here we are, largely because the manufacturers are much like PC makers in that they put their own interests far ahead of the ecosystem interests.