Google+ had terrible marketing and release, but it had some decent ideas that I wish other networks had carried over. The idea of "circles", where you had a circle for "acquaintances" "friends", "family" would be great on, say, Facebook, as it would allow me to filter down my feed to just the people I really care about but still have a connection to more distance acquaintances. Currently on Facebook the news feed is…
Microsoft is the biggest offenders in this, since time immemorial, with an almost sad sort of attention-seeking "Look look we made this!" by prefixing every product and service with their name.
Of course I see why they would want to do this; it entices your existing fans to check it out and bolsters confidence.
But the problem is that your company's reputation and "image" is then immediately projected onto your new product before anyone even tries it.
In Microsoft's case it's their sterile 90s-suit-and-tie-office-workplace, wannabe-cool /r/fellowkids image (in my view at least.)
Even Apple does this and it adversely affects their new products too (like Apple Music) for people who hold some kind of brand grudge against them.
I and I'll assume many people use Google out of necessity than any brand loyalty, and in spite of disagreeing with their privacy-hostile core model. If they hadn't bought YouTube and if other search engines were as fast and provided as relevant results (though Google Search has been slowly crapping out in that regard since the past couple years), I would be using no Google products or services.
Google were hardly associated with the word "social" and "Google+" doesn't say anything about anything social. The first impressions of most people when hearing about it very probably did nothing favorable for the service.