I recommend reading John Stepper's excellent new post, "Your best use of social media may not require a single post." Although John's post is about regulated industries such as banking, it touches on an area that many social media professionals find ... touchy.
Here's the rub: Ask most social media pros how they judge the success of a post and they'll tell you by the number of comments that it generates. Many people consider comments to be a valid proxy for engagement and interest.
Personally, I don’t believe that comments are a valid proxy for engagement or interest. The content you post has intrinsic value whether lots of people or few people — or no people — reply. Not every piece of information you post has to inspire a dialogue to get the job done.
Seems to me like a variant on the old, “If a tree falls in the forest and no one hears it fall, does it make a sound?” Yes, of course it makes a sound, and yes, when you post content on a social collaboration platform, that content has value — even if it does not result in a social conversation that can be tracked and quantified.