What's immediately striking about Trajan's quinarii is their remarkable thematic consistency. The vast majority of Trajan's quinarii feature the goddess Victory on their reverse. As with those struck by other rulers, the quinarii of Trajan are quite scarce. Not many were struck, and due to their low monetary value, were not saved in bulk. Therefore they are rarely found in hoards. In fact, most are found individually. This makes it particularly challenging for modern collectors to complete a set. Additionally, the rarity of Trajan's quinarii reveals their purpose. One school of thought suggests that quinarii were struck as ceremonial issues and weren't intended for everyday circulation but rather as special commemorative pieces or gifts distributed during triumphs, consulships, or other state celebrations. This theory is bolstered by the fact that they did not truly fit with the contemporaneous monetary system.