The settings to keep an archive of the list:

(a) If the list is not to be archived, the setting at Archiving Options > Archive messages? is selected as NO.
(b) If the list is to have an archive but only to be seen by the list members:
    (b1) The setting at Archiving Options > Archive messages? is selected as YES.
    (b2) The setting at Archiving Options > Is archive file source for public or private archival? is also selected as YES.