The customer is asking if there is any place in Sitecore where a content author could add internal notes for an individual version of a content item. The note might say something like "I changed the content field to include updated descriptions" or something. This is different from simply adding a comment when you submit an item in to workflow. They want the ability to look at different versions of content items and see what the different changes were easily with comments and specifically why content was changed.
Does anything like this exist in Sitecore out of the box?
Corey