I never considered a difference of opinion in politics, in religion, in philosophy, as cause for withdrawing from a friend. – Thomas Jefferson
If you read discussion boards or listservs on the subject of singing, you will eventually witness discussions about people’s favorites – singers, genres, vocal exercises, teachers, repertoire, health tips, and many other things. The opera queens, in particular, can become very combative about their views on “great singers”. Any question beginning with “Who is the best singer…” is not answerable. Truly liberated and able voices are unique and cannot be compared like manufactured objects. (We have a problem with so many voices in ALL genres sounding like manufactured objects, but that is slightly off topic.)
It is much more enjoyable and informative to argue for your favorite as a favorite, rather than proclaiming them to be “the best…”. Others will enjoy hearing your reasons and some actual examples of the singing that back up your opinion, not your rating per se. Also, labeling something as your “favorite” is in line with the current “fair fighting” practice of using “I” statements. “Favorite” inherently means “to me” or “in my opinion”. “Callas is the best; Tebaldi was a hack.” is a conversation killer. It can cause polite and meek people to close down, while the opinionated people expose their fangs and enter the ring.