As we all look forward to the upcoming Source-A-Thon, we begin thinking about unsourced profiles -- those in the Unsourced category or that are marked with the { { Unsourced } } Research Notes Box.
This is not a post intended to discuss what qualifies a profile to be categorized as Unsourced, or what is a "good" source.
The criteria for categorizing a profile as Unsourced are described here and here.
There are many profiles in the Unsourced category. To find unsourced profiles to be improved see the Data Doctors Unsourced Report, which is updated weekly or the Unsourced Profiles Category.
I have long thought that there are many more profiles that could possibly be categorized as Unsourced, have written some software to test this theory, and applied it to a small portion of the WikiTree profiles near the middle of August 2020. Any profile found, of course, needs to be reviewed to see if the Unsourced category is appropriate. There are a few thousand such possibly unsourced profiles listed on the Unsourced Profile Hints space page. The description on that page attempts to answer FAQs.