And the pixel c that just released
PIxel C is another experiment/project. You guys must not read or watch much of what Google does or like to read Rumor reports a lot. Google is not your average company like Samsung or LG, they do things differently. It is a set pattern and it hasn't changed much. They are one of the easier companies to know about, because they are very communicative in what they are doing.
These devices are not intended to make Google a bunch of money, to take over Samsung, LG, or anyone else. Their primary reason for existence is get as many people as possible using their services (collect data), secondary is to promote Android, third is to show by example of what can (should) be done to other manufacturers, fourth to use Nexus as a test bed for new services, and lastly is not lose any money in the process.
This is why form one year to the next, it is not even known if Nexus will produce a phone. Selling phones is not their business model.