I dont Understand why do people degrade the opponent of their favorite fighter

Reading the threads of both Pacfans and Mayweather fans, I don't understand why you guys degrade your favorite fighter's opponents when that does them no good, by saying that either Pacquiao or Mayweather are overrated, bums, cherrypickers and whatnot puts your fighter in a no-win situation, if he wins, where is the glory in beating a cherrypicker, onedimensional, overrated fighter? and if he loses, he would have been beaten by a cherrypicker, onedimensional, overrated fighter as well. The same thing happened when Pacquiao fought Cotto, Pacfans said Cotto was damaged goods, among other things, then when Pacquiao won they tried to hype the win over but the damaged had already been done and many fans still don't give Pacquiao credit for that win because of the previous comment by the pacfans. So stop putting your fighter in a no win situation.