Well i don't count guys before the super bowl era as the tape of them isn't good and the game was very different back then.
How i do my top 10 is i ask this question. Who is the most likely to win me a super bowl? That means who will get me to the playoffs, play well there and be clutch in big moments. Of course stats, wins, rings, and certain X factors are part of all of this.. but they are all used in the service of trying to answer this question. Now you don't need to win automatically to be ranked, but proof of concept (multiple times even) can be a huge plus. But I don't just count rings either.
#1 Brady
#2 Montana
#3 Mahomes
#4 Staubach
#5 Elway
#6 Unitas
#7 Manning
#8 Starr
#9 Brees - Realistically Rodgers should be over Brees but he is just so bad in the locker room, and Brees tends to be more clutch.
#10 Rodgers
HM - Starr, Young
Those are the 12 I think really stand above the rest.
I know some people will freak about about putting Mahomes that high already. But is sample size or more or less as big as Staubach, Starr and Young who people put up on all time list. And he has done more than all of them.