The key to adding a generation to your family tree and thoughts on quality ratings

The crucial issue with any individual entry in the Family Tree is if there is a valid historical source (record, document etc.) showing a parent/child relationship. Absence of this important documentation means the person without a continuing source for a parent/child relationship is essentially the end of the line, not a child of the family, or is not a sibling. I certainly understand about beginning genealogists adding information from their composite family memory, but these living and recently dead people are usually easier to document. 

The issue of the absence of a document showing a parent/child relationship is extremely common in lines on the FamilySearch Family Tree that go back into the early 1800s and 1700s. I find this end of line almost 100% of the time when I see one of these lines that wanders back into the Middle Ages. To make this clear, the end of the line on any ancestral line occurs when there is no document showing a parent/child relationship. 

So any quality rating that does not include some way of determining this basic relationship for moving back an additional generation is incomplete and needs further research. Records that could show such a relationship to the next generation include birth records, probate records, land and property records. military records, tax records, census records, and many others. 

In addition, continuing research for additional generations based on one document is also a very bad idea. The main reason is the prevalence of people with the same name. The accuracy of the family tree rises and falls on this one simple issue. 

Here is an example of an ancestral line that begins with this person who has NO sources and continues for generations: Edward Morgan L4Y1-F4P.  The Family Tree shows 17 or 18 or more generations back from this one person without a source record who was married in Shepherdstown, Jefferson, West Virginia, United States up to a hundred years before any of these places existed except Shepherdstown that was established on December 23, 1762.  Jefferson County was established in 1801 in Virginia. West Virginia did not exist until June 20, 1863. This is just the tip of this messy ancestral line. The last person in this line without a further generational parent/child relationship is Garrad Morgan L7GZ-YBB who was born in 1755. He is the "real" end of the line that stretches back more than twenty generations. It doesn't really matter too much at all that the Quality Score for L7GZ-YBB is Medium and his non-existent father GM8Y-L9D is also Medium and does not exist.  I do think the ratings are helpful, but do not yet assess the accuracy of the entries.