One guys 22 and the other guy is 30, one guy has seen several Nog fights and analyzed how he got beat.
Not really rocket science as you get older you slow down by a few split seconds which is the difference between a win and a loss. And when your a famous fighter 12-15 year olds eat sleep and breath all your techniques then turn 20 show up and clean the floor with you just like Matt did to Gracie.