They let Android be turned into whatever others wanted it to be, and maybe they promoted the Android brand, maybe they didn't. And if they did, they tried to "own" it. But mostly they've tried to mention it as little as possible, while promoting their own stuff.
Google should've never let this happen. They should've treated it the same way they treat the Chromebooks. Nothing gets changed in ChromeOS unless Google says so. And everything works the same across Chromebooks. All upgrades come from Google for all Chromebooks, and every 6 weeks. It's tight and it's clean. And they get to promote the brand.
But Android is the opposite of that. Google has no control over 99% of the Android devices when it comes to upgrades. This is terrible for users, terrible for developers, and terrible for the security of these devices, whenever there's some big security exploit. Okay, Google can still uninstall apps from your phone in case something like that happens, but they can't really fix the issue usually.
Android should've been run like Chrome and ChromeOS from the very beginning. They should've had the "main brand" (like Chrome), and then they should've had the "open source brand" (like Chromium). Google only ever promotes the Chrome brand, and now that's what OEM's and customers want. They want Chrome. They don't want Chromium.
They missed that opportunity with Android. Android should've been the main bran that Google owns, gets to modify, and updates. If they would've done that from the beginning, then OEM's and customers would've also wanted the unaltered Google-owned Android, rather than the "heavily-customized open source brand" that Android has turned into, and is the main choice for virtually every OEM. So the Android world is like a bizarro world where "Chromium" would be what most OEM's and customer want, not Google's own Chrome.
But there is still time to fix that - by expanding the "Chromebook-tight" Nexus program. Get Nexus become to Android what Chrome is to Chromium. And then try to make 99% of OEM's and customers to prefer the Nexus over the heavily-customized open source "Android". This will probably take 5 years or longer now, but I think it can be done. Even if half of the market is "Nexus devices" 5 years from now, I think it will be worth it.
Of course it would've been much easier to do this from day one, since now they have to fight and uphill battle, and "unconvince" OEM's that they want to use the "Nexus OS"/stock Android, not their own customized stuff. But slowly, they can convince customers to buy those, and in time the OEM's as well, if that's what the people want.
So if they are indeed applying this strategy, then that's good. I've noticed they are promoting the Nexus devices lately. Now they just need to get more OEM's on board (not just one at a time). That would give people more choices through out the year for Nexus devices. Some may like the Nexus, but if they want to buy a new phone 4 months later, they might just get the latest Samsung or HTC device, because they'd still prefer a newer phone.
This also needs to happen for low-end devices. I want to be able to buy my mom a very cheap Nexus phone. I'm thinking $100-$200 range here. It can be done with Cortex A7, a decent 720p capable GPU, and a 800x480 resolution display. It should be good enough performance wise, but Google should still make sure these devices aren't very buggy or something. And they should handle the updates for them.
A good way to start pushing more "Nexus" devices in the market is by getting Motorola to use only stock Android. I think they'd be really stupid if they aren't doing this. Their customers want them to do it. Screw the other OEM's if they get upset about it. They're free to join the Nexus program (and they should be), and use stock Android, too. They'll come around if Motorola shows there's a market for that. So Google needs to stop fooling around, and start being serious taking back control of Android with the Nexus OS/program.