Consider Quora. When I look at my stats there, I can click on a single day, and see a list of the articles/comments that made up that day's data. When I click on a single article, I can see how that one article performed over time. I can look at only articles with certain tags, to see if certain subjects outperform others.

With Medium, if you want to do that, you have to download all your statistics to a spreadsheet and crunch the numbers yourself. It is not at all user friendly. If, for example, you see a sudden spike in views, you have to look at all the articles you think MIGHT be contributing to it, and check each one individually. And if something you wrote weeks or months ago has suddenly gotten traction, you'll be looking through your details pages for a very long time.