I have seen a few websites that compensate writers come and go. One of my favorites was Gather.com. Just when I started really connecting and achieving success on the site it went bye bye. Often it happens because of business dealings behind the scene that changes how the site operates when the site becomes popular. Although I love medium I do not recommend anyone to depend on it as a form of steady income because these types of sites seem to be fickle and the rules can change at a whim. I do believe that you will have a good year here on Medium and just continue to take advantage of the opportunity while it lasts.