There are two different cases available in your academy’s settings:
1) Courses are suggested by default only based on permissions that have been set up (i.e. what roles have permission to access which course categories). This means that by default users are suggested the latest courses that have been published and are open for them to take.
2) If you want the system to suggest courses to end users based on more criteria like their role or skills needed for their role you can choose to turn on this feature and configure what criteria and weighting factors (i.e. priority) should be taking into account. In order to leverage the suggestion algorithm you have to set up correctly the associations between skills, roles and courses in the skills and performance management module.
If the first option is enabled, then:
In general the first criterion is when a course was published, and the second is when it was created. So the four latest published courses would be shown in general. If courses were purchased with a coupon, then those would have priority over both aforementioned fields.