Actually there is a perfect science to it, you just happen to be too dumb to understand.
Fedor won the world HW belt in 2003 against the #1 HW in the world at the time. That was as big as winning the UFC HW Belt today AKA the pinnacle of fighting. Fedor then won his next 9 fights with wins over Nog,Coleman, Randleman, Fujita, Goodridge and Kohsaka.
in 2005 Fedor won his 10th straight fight since winning the Pride FC HW Belt. It was the biggest fight of his life, his 24th career fight and he was absolutely in his prime at that point. The only way a person could disagree with this is if they are a dumb kid like you who just wasnt around at the time.
By 2006 no one wanted to fight him not even Barnett at Shockwave.
By 2007 the sport of MMA was going through a major transition stage and Fedor wasnt fighting much at all because he was a free agent and the UFC had trouble signing him after the buy out of Pride.
By the time he was in Affliction it was already 2008 and Fedor still had some flashes of brilliance but that same year he lost in Sambo to Ivanov, and then in 2009 his coaches were saying hes slowing down and then he looked pretty bad against Arlovski and looked bad against Rogers and anyone who watched his career could see he was on the downside and past his prime.
He finally lost to Werdum in 2010, 5 years after his prime.
See, its not that hard. My son of my 5th mistress.