I don’t need four repairmen coming over, I just need one who knows what he’s doing.
Citation and documentation matter in genealogical research. But “sources” are more than just citing them and the number of them you in an attempt to prove a fact about a deceased relative. It is the accuracy of those sources and whether or not they are truly independent that matters.
A person may have four original documents that provides the same piece of information: a place of birth. But if those documents (a death certificate, a marriage application, an obituary, and a biography written by the same person) all have the same informant, it’s really just one piece of information that is dependent on how reliable that person is.
A place of birth on a birth record completed by the doctor or someone else in attendance at the event or who would have had reliable first-hand knowledge may be better than numerous other sources written by someone whose knowledge of the event is second hand–especially when those sources did not agree.
It’s not how many sources you have that is as important as their perceived reliability.