Your fellow-hubbers are most likely to leave comments. They are ones who are more likely to have a common relationship with you as followers or writers with similar interests.
If you write on controversial topics, you are likely to get more comments.
Also-- if you answer each, or most, comments-- your comments are also counted.
Readers who come from outside searches, Google and others, are less likely to comment because they are mostly here from searches of subjects they are interested in. They come for the information, or seeking something to buy. They may like your writing, but most will not comment.
The ones that come in from search engine or referral traffic are most likely to to benefit you financially.
So the percentage of commenters is not a measure of success.
As to Becky's answer-- you have a 100 score at the moment, so someone must like you.