Riots favoritism for certain champions is so obvious.

"One of the jungle's flashiest all-stars, Lee Sin's become a rare sight in the professional scene as of late.This means that although Lee Sin is still one of the strongest champions when you want to gank lanes, falling behind other premier junglers ever-so-slightly in health could mean all the difference when a fight breaks out. We're nudging Lee's sustain up a notch to keep him healthier in those crucial early levels."

LIFESTEAL AND SPELL VAMP 5/10/15/20/25% ⇒ 10/15/20/25/30%

The second they nerf damage creep (they might never) Lee sin is going to be the most broken as hell jungler youv ever seen and i doubt they will revert this buff.