Ben Marcus said this quote

The American Naming Authority, a collective of women studying the effects of names on behavior, decrees that a name should only have one user. The nearly 1 million American users of the name Mary, for example, do not constitute a unified army who might slaughter all users of the name Nancy, as was earlier supposed, but rather a saturation of the Mary Potential Quotient. Simply stated: Too many women with the same name produces widespread mediocrity and fatigue.