User blog comment:KingFubuki92/The Issues with RWBY's writing, and how Volume 6 can possibly improve on them./@comment-71.30.17.231-20180123235423/@comment-34633327-20180124000128

The Maiden naming I think was more their original naming becoming their titles. The World of Remnant for the Maiden's had each one of the four sisters bare the name of one of the four seasons, each one showing up at Ozpin's cottage in their corresponding season. More than likely they are named after the seasons in memory of the original four. I could imagine that the word Maiden was initially more of a title for each one, like "Maiden Spring", or "Maiden Winter", but when new ones started showing up, they began being called "Spring's Chosen Maiden" or "Winter's Chosen Maiden", before it was just shortened to "Spring Maiden" and "Winter Maiden".