You know, I owned the Motorola Moto X, which Google collaborated on. Much of the phone flipping gestures and always-on display features have originally debuted on the Moto X.
It was a great device software wise and that made up for the rather unimpressive hardware. I also know someone that owned the Nexus 5 which came right after the Moto X. Also a very impressive device.
I don't know what happened, but Google used to make(in collaboration) good phones.
Before the Nexuses, Google cooperation enabled certain OEMs to deliver some pretty nifty devices indeed. The Moto X was a very good phone in its times.
I believe the problems started when Google decided to take the matter in their own hands - which makes perfect sense from a certain point of view, being nothing less than Apple's playbook, to own both the vertical and the integration. Problem is, Google is not Apple. Google has the attention span of a hummingbird towards their projects, and has proven over time that anything can be binned; while Apple used to have a manical attention to details (which has somewhat declined in the past 10 years in favour of style for the sake of style, e.g. the awful butterfly keyboard), Google is a pure engineering company. It is my opinion that it's just not in Google's DNA to stick to a product (like a mobile phone family) that requires dedication across several generations of development, and they don't have the know-how required to put things together.
Building great mobile phones can't happen overnight, no matter the amount of engineering prowess, and Google is proving it... the hard way.
That's a great explanation. I agree Google is known to abandon projects rather quickly. I'm not excited about phones as I was a couple of years ago, but even then the nexus lineup was pretty bland.