After completing a course

Maybe I missed where it said what to do, but what am I supposed to do after completing a course? Do I go back to the selection of courses and get rid of the completed course or is there something else I have to do? It says I completed it 100%, so I thought it would've been gone on its own. I have nine active courses, and I completed one recently, and unless I figure out what to do, I can't replace it with a different course. Perhaps I'm overthinking it and I do have to get rid of the course, but I would like confirmation before I do that. When I signed up for the courses, I assumed that when a course was completed, the lessons would go away and there would be a list or something that said all the courses that have been completed. I'm not disappointed that there isn't; I'm just confused.