PBE is used for testing bugs, not for balancing Champions.

The sooner one realizes this fact, the sooner they can understand Riot's logic when it comes to balancing. For one, they have millions of subscribers and this is based around being free to play. Which means they lose absolutely no amount of money on an individual who chooses to quit the game. All of the money they would make, comes from RP, which is through skins and other little things such as ward skins, champions, rune pages, etc.

How does this impact their ability to balance the game? It means they can balance the game to whatever suits their needs and desires. Is a champion dominant in LCS but weak in Solo queue? They can choose to let the champion remain at their current state as LCS helps them gain more money. (Lee Sin) Or they can nerf them for overcentralizing such as Leblanc.

Is a champion dominant in solo queue but weak in the LCS? They can choose to nerf that champion (Evelynn) Or they can choose to nerf the champion. (Some example I cannot remember here.)

Ultimately it falls down to how Riot views the champion, how it will impact the vision of their game, and if this is acceptable.

This is also why win percents are completely and utterly meaningless. Not only because they fail as a statistical measure of balance, but also because it has no meaning to the above.

[slayer-pantheon-popcorn]