Why is Gragas banned so much?
According to champion.gg, Gragas has the 57th best winrate in Platinum +. It makes me wonder why he's banned at all. He may be annoying but there are dozens of champions performing much better on average. If people ban champions to increase their winning chances, the high Gragas banrate is irrational.
BTW: I do realize he got nerfs in 5.10 and I'm not suggesting that he isn't a great jungler.