For poetry — honestly I don’t know. I have not met many people who try poetry on Medium, and most of them write other things as well so it’s hard to judge. I’d guess the same rule applies, though. The more you write, the better you get. The better you get, the more people will like your stuff. And on, and on.
In my opinion the main thing about inconsistent reads is inconsistent writing. It’s hard to always be good. Half of the things I throw up on Medium are crap, or at least not great. Even if you only put up your best stuff, you are probably not keeping a consistent quality because inspiration is hard to come by! The things that are great get thrown up on Facebook pages, bandied about on twitter, and put on sites like flipboard or smartnews. Those are the ones that get hundreds or even thousands of reads.