Yes, I know what you mean.
I just asked for input about this on Facebook a bit ago: "Facebook I get. Twitter I get (though I don't use it). Google + I get (though it's a wasteland these days). Pinterest I don't get at all."
People explained, I kind of got it, but I still can't seem to really use it the way it's intended.
I'm doing an overhaul of my desk area and it was useful as an actual pinboard -- that is, putting various things together and seeing how they looked.
But then I kept adding photos of my own actual things that would be included, rather than pinning from elsewhere, and it kept getting further from what Pinterest is supposed to be I think.