Basing nerfs/buffs on win rates and ban rates appears to be scientifically invalid method

Win rates of champs and ban rates of champs are supposedly the determining factor for when champs should be nerfed or banned.

This IMO, is scientifically invalid.

Win rates on team games are driven by player participation and drive. This is not a direct quantifiable way to measure effectiveness. For instance, Yorick, hardly picked, yet most would agree his Ult, summoning an ENTIRE EXTRA PLAYER on the field with 5000 HP, should be nerfed.

Ban rates on champs are driven by emotional drives of the player community. Just because a monster champ isn't banned doesn't mean the monster champ shouldn't be nerfed.