After giving a week in finding reason for failure or earning very less on steemit, I am able to put light on certain points.
Very first thing, you might have noticed that someone get 100s of upvote and 100s of comment but didn't earn a single $. While on other hand there many who earn many $ with few upvote and comments even with same reputation. One more thing you might have noticed that you have 1000s of follower but reputation is around 40 while someone with very less followers have reputation above 60.
This happens mostly when we try to adopt vote for vote, comment for comment and follow for follow system. There are many groups of social media where people try to create such group and follow this tactic. But system detect this tactic as you are getting upvote, and comments from same blog again and again, hence your earning potential and reputation is decrease.
More over the upvote or commentor is landing on your post directly from other website, he just upvote, comment and close the page. So don't use these tactic this will result in failure. The key to success is write great and engaging content, upvote and comment only if you like the work of other.
The above all points are my personal opinion if you have any suggestions or correction kindly mention in comment.