It's actually a garbage role. Not for the reason most people think though.
The issue is that its universally agreed that "JG influences lanes" but that is NOT the case. Lanes determine what a jungler can and can't do.
If a lane has priority and the laner knows what to do, that opens up the jungler to get vision down, invade, and control objectives. If the laner doesnt know what to do with their priority then an invade can go horribly wrong because your laner didnt raom when they could have and should have. This makes it a coin flip when invading unless you KNOW your laner will roam or you have a clear 1v1 advantage on the enemy jungler.
If lanes dont have priority then the exact opposite happens, the enemy jungler can do the invading and objective control. If your laners cant help, you are forced to give up your camps on one side of the map. You are FORCED to play safe because you have to assume the enemy jungler knows what to do when his laners have priority. In a lane you can feel out how good your opponent is. In jungle you have to assume they are perfect players or risk losing your whole jungle AND dying.
Vertical jungling works assuming you have at least one lane with priority that will roam if needed. If not, the enemy now has all of their jungle and half of yours.
Ganks are down to whether or not your laners play it right, call out where vision is, layer cc properly, shove the wave for the dive or freeze it for the gank... none of this is under your control. It's 100% on the laners to know what to do.
There is no consistency. You have to adapt to what your laners do every game and the skill of your laners changes every single game. If you gift your top 2 free kills but they are bad, you just wasted a ton of time ganking their lane AND giving shutdown gold to the enemy top laner. You probably lost the game off that.... even though you played everything right, if your top laner cant use his advantage you will lose the game since you put all your time into getting them ahead. It's a coin flip.
Yes a lot of this is true for a laner too, BUT a fed laner is INFINITELY stronger than a fed jungler and can forcefully influence the rest of the map if they know what they are doing. A jungler is always at the mercy of its laners.
People always say "junglers decide my lane" NO. You decide your lane. If the jungler got the perfect gank off at just the right time it's because YOU all inned at the WRONG time. You didnt have vision down, you weren't tracking the enemy jungler based on where they started or camps up, you got greedy to push one more wave, etc. YOU did something wrong as the laner that got ganked. The jungler just capitalized on you messing up or your opposing laners being better and setting it up perfectly without you stopping the setup.
Mix all this with the fact that you can be playing perfectly, have a 40 cs lead on the enemy jungler get off perfect counter ganks to deflect their aggression then watch them successfully gank bot lane through full vision and back pings, pick up a free double kill and first blood tower.... Now you're at a huge gold disadvantage and have to give up your bot side jungle and drakes for the rest of the game.
IMO the fact that what you can do as a jungler is almost 100% in the hands of your laners makes Jungle a horrible feeling role to play. ESPECIALLY because laners dont understand this and believe you can do whatever you want whenever you want as a jungler.
If more laners understood how lanes influence what junglers can do then jungle would feel much better as a role.
