It rapidly became clear that the burdens of curation of circles and figuring out which one to use made using GP too much effort. FB does have a mechanism like that but it's barely even known about, while the coarser "group" mechanism does seemingly 95% of what people would want out of circles.
One might consider it an example of "worse is better", though I'm not convinced.
(Wow, just checked and Google+ is still available. I'd thought it had already shut down like Orkut and Wave).
In so much as Google added to "the burden of refinement", in some ways it didn't go far enough. If someone I know posts cat videos and boardgames reviews, and adds me to both Google+ circles, how am I to subscribe to one and not the other?
This problem is bidirectional: which posts of yours will you let me see and of those, which do I want to see. But this is an even heavier ask.
One might consider it an example of "worse is better", though I'm not convinced.
(Wow, just checked and Google+ is still available. I'd thought it had already shut down like Orkut and Wave).