As a user, it absolutely does not matter “why” to me.
I see a new google product. Should I spend time getting used to it?
A service is provided by Google or a third-party app. Should I choose Google “by default”?
I recently spent a few days trying to get google cloud print to work. It will be killed in a few months. Do I care why - was it replaced by competitor’s product, was it non-monetizeable, was it for the good of other developers? Nope, I don’t care.
The main point of this website is to illustrate that Google products, even if nice and polished, sometimes live much shorter than desired. And website does this splendidly.