There are hundreds of options for champions to play and even more choices on how to play them. In an ideal environment, all available options would be relatively equal to the rest. However, this is an impossibility. When presented with so many options, especially in a competitive format, certain options will prove superior to other options and people will naturally choose those over others so as to maintain an advantage over or, at the very least, equal footing with their opponents. When some options prove too superior then those options are generally "nerfed" in a vain attempt to provide balance to the game, whatever it might be. But this does not balance the game, it merely shifts power toward other available options and players who wish to continue maintaining a positive win rate will then have to adapt and shift towards what constitutes as the "new meta".