The Australian honours system is based on chivralic heraldry – with upper and lower ranks – following the template of imperial UK honours and endorsed by our Head of State herself. In this system, the contributions of some awardees are deemed to be more important than those of others; some high ranks are awarded as a matter of course eg to former Prime Ministers or those taking on the roles of State Governors who from 2013 to 2015 were given knighthoods or became dames. Volunteers almost always appear in the lowest and most common rank, the Order of Australia Medal, OAM. Jenna Price has nailed it in this article (linked below). Her conclusion that the honours system needs an overhaul when we become a Republic is spot on because it will then no longer be fit for purpose. [“Honours System needs a Rethink” by Jenna Price, Nine media online 14 June 2021]