Because the homepage is the most expensive real estate so speak and the system admin can’t put every course created on the page. For sake of design and page load, it has to limit a number of courses allowed on the first page. So when creating the course, there is a checkbox for you to check to request the system admin that you wanted your course to list on the first page of the homepage. This means that there could be two possible reasons that you don’t see your course listed on the first page. One being that your request has not been approved or two you didn’t ask the admin to do so. However, you can search all published courses. Just remember that for security reasons, every course is required approval by the admin before it’s published to the public.