I recently learned that there is a dust threshold on Steemit that makes all post or comment earnings (and curation rewards) worthless when they are below 0.02$ as a way to combat spam. (read This Post from @fullcoverbetting about it.) I also have upvoted comments on my post often with 0.01$ often just to show that the comment has been read these past 8 months without knowing about it.
Check back on posts that are 7 days or older and you will see 0.00$ on comments you kindly upped for 0.01$.
** I assumed a 1% upvote would get your 0.01$ comment worth up to 0.02$ but it didn't, maybe when the price of steem goes up a bit it gets there.
It can go one way or another, a 1 cent comment can become a 2 cents comment. Thank you for commenting and sharing a link to a post. If there is a threshold, then I will try to vote over it.