This setting allow to choose those leave types in the drop-down menu only for the roles they were set for.

For example, administrators were set up on a certain leave type:

• This type will be shown only on the administrators’ drop-down menu at the time-off request page as well as the detailed attendance report
• They can report it on behalf of other employees 
• Other roles will not be seeing this type on the drop-down menu, but when chosen for them they will see it on their timesheet as a non-editable entry

Go to “Settings” -> “Company profile” -> “Absence types” tab -> Check the box “Allow only to the following roles” for the relevant leave types -> Select the roles you want to enable this type for -> Click “Update” to save