Most of the comments on steemit are of course writing, I see for myself this phenomenon. Many reasons are found, first because it posts a friend, so must comment without knowing the contents of the post. Secondly because it is asked to comment by who has a post, the results are not in accordance with what is in the post.
Obviously as the owner of the post wanted to comment it in the form of criticism or input, so that our writing can produce more on each post.
I hope in every post I have criticism from any readers who have seen and read my post.
It rarely exists, indeed we need to remind each reader to give criticism and entry, in order to improve the quality of our writing.