For me it's important to know that someone has actually engaged in the content provided. I want to know that what I took the time to write, compose, and add to the platform was worth a comment. It means more if people are actually thinking about what you present than just simply fishing for followers, votes and money, or at least it does for me. I can't really speak for anyone else, but if I am going to read something then nine times out of ten I will leave a comment to let the author know what I thought about the material and what if anything I can add for whomever else may be reading. After all it is, social media, right? Without the social interaction it would seem rather bland, much to be desired.