One site has a universal family tree–ideally with one record per person who has ever lived–and the others host individual trees for each user, leading to lots of duplication.
Here’s one example: how many records are on each site? Some sites include DNA results and user-submitted family tree profiles in their total record count. Others don’t. One site has a universal family tree–ideally with one record per person who has ever lived–and the others host individual trees for each user, leading to lots of duplication. Does a birth record count as one record? FamilySearch thinks so. But other sites may count a birth record as three records, because a baby, mom and dad are all named. So it’s not easy to compare historical record content across all the sites.