When creating a new Author profile in Arc, the Username field (which is required) allows for anything and everything to be inside of it. So even though we want all of our authors to follow a pattern like "firstname-lastname", editors are putting all sorts of things in that field. Some put in an email address, some put in byline names complete with spaces, some contain punctuation.
This is a big problem for us because we now have several authors with profile pages that are broken in various ways. The most common issue is that some authors have pages that include stories from a variety of other authors on them. For example, this author with the username "Everton Baily Jr.": https://www.dallasnews.com/author/Everton%20Bailey%20Jr./