there's something that's been bothering me since I started playing League a few years back, and since I assume you read the title, you know what I'm gonna rant about.
Jungler - a powerful role in the game, often times the role that decides victory or defeat.
Good jungling is not easy by any means. You have to keep track of the enemy jungler, which lane is ahead, behind, where are the enemy wards, when to try for a dragon/baron/herald, when to invade/fight or back off and stay safe, are just a few of the things they have to keep in mind nearly all the time.
Based on all these parameters they decide which lane to gank, when and how often.
And then there's a Zed mid, who dies to an enemy gank, and proceeds to blame his own jungler for his lost lane until the end of the game (and then some), because you didn't intercept the gank, or gank back.
Would the outcome have been different? Likely. Should the jungler have ganked Zed's lane? Maybe. Was he obliged to gank Zed's lane? NO.
Just because you (in the role of the aforementioned Zed) aren't doing well on your own, doesn't mean your whole team should hop to your aid when you snap your fingers. While you sit on your lane convinced that your jungler is the source of all your problems, he/she has to find a way to carry your ass, whether means ganking your lane or others, or none at all, it's not YOUR call to make, it's theirs.
The way I see it, ganks are a privilege. You are pitted against an opponent in lane, and you have to do your best to win on-your-own. Expecting a gank is like counting on the weather to change to something that suits you better - it's either going to happen, or it's not, and you have to play on either outcome.
It feels like a lot of people take ganks for granted, and are therefore angry when they don't get any, similar to a spoiled kid not getting his chocolate bar.
I'm not a jungler myself, and I'm not saying all junglers are masterminds and that you shouldn't question what they are doing, just consider their position from time to time. Maybe they aren't ganking any lanes because they are behind, and ganking would likely only end up giving the enemy a bigger lead. Maybe they are camping bot and ignoring other lanes so your adc gets fed and carries the game. And maybe they just have no idea what they are doing, but that's not something you should assume right off the bat.
If I sum this all up; play on lane like you have no jungler, and appreciate it when they DO show up and help you out.