Best is only measurable by what takes place on the field. Any notion of "best" beyond what is measurable is not empirically supportable. To make the claim of who is "best" independent of empirical findings is to engage in pure fiction, imagination, it's to satisfy biases, to reawaken predetermined notions or to dangle an imaginary concept above actual results, thus allowing people to make claims that exist in complete contrast to what takes place on the field. All we have is our perception of who is best, that is the only thing that has any epistemic merit because it's based on what we've seen take place on the field. Right now, the best teams are: 1) Georgia, 2) Cincinnati, 3) Michigan State, 4) Oklahoma. Those teams have not lost.