Medium is a powerful blogging platform. It allows anyone create its own blog and publish blog posts. Specify a few hastags and hopefully your ideas will get discovered by other writes & readers.
Your Medium articles will be indexed on Google. For that reason the main share of the traffic to your article will come from the search engine. But between 5 and 30% of your readership will come from internal traffic: Medium users. In order to maximize this they are multiple things you can do:
Engagement pods will help you get the initial boost to have your content seen. This boost has to happen pretty soon after the post publication in order to send a signal to Medium: "This content is valuable, people are clapping it so feature it more on the home page". The content will be featured more to unknown readers as well as your followers in the "From your Network" section.
Another big way engagement pods will help you get visible is by giving you authority: It's human nature to give more credibility and trust to data that has been approved by others. A Medium engagement pod will have each member of the pod clap 50 times for every article you publish. Getting your first 1k clappers will dramatically increase your article visibility and authority.