How are comments useful on a blog???

Comments are useful on a blog because the author can know whether or not their blogs are useful or not; and the viewers can give their opinions on whether the blog is useful, interesting or pointless!  Being able to understand how other people feel about their comments, the author can make changes that will improve the quality of their blog.  Although there is always room for improvement, the author is given the opportunity to find out what is good about their blogs and make them more interesting!  If the blog was about a debating topic, one would be able to debate with other users on the topic and come to some conclusions or just have an interesting converstation about both sides of the argument; however if the blog were about a business or company, the author would then be able to use the feedback to think of ways of improving or changing it's companies image!  Either way comments allow for the author to change and imrpove their blog.