This register is populated with purposes you have defined for a specific agenda. They can be generated automatically (upon record creation) or manually (by clicking the Generate purposes button in the Purpose definitions register), depending on the settings of the given purpose definition.
In the screenshot above, we can see automatically generated purposes from payroll (cash on delivery, advance tax, social insurance, health insurance). In this case, the purpose definition is predefined with the name "Other liabilities – Accounting Act/VAT Act"
with the controller relationship type.