Sometimes we make changes that are correct for one song / one album but may cause issues for whole collection. Because there are often good reasons not to run Fix Songs over whole collection, better to add a separate simpler task for dealing with these issues.

Multiple different people with same name (artists/composers ectera). MusicBrainz has a disambugation field that it uses to differentiate between artists with same name, however a user doesnt want to see this unless in their own collection they actually have two different artists with same name. So the idea is we scan collection, look for occurences of duplicate people with same artist name but different mbid, and if found apply diambuguation