I know it isn't popular to suggest nerfs for champions, but 
has had a top tier win rate in Solo Q at all levels of play for years now.
Honestly, why does she have the largest mana pool/best mana regen of the supports? Her mana costs are high, but poking her so she runs out of mana so she can't use her shield should be a viable strategy. As of now, it's not because poking supports will run out of mana before does.
CCarnage3 votesA good thresh / blitz will ruin Janna's day in lane phase.
Sogreth6 votesA good thresh / blitz will ruin Janna's day in lane phase.
Maybe Blitz, but Thresh is garbo against Janna. Unless her ADC is a brain dead Wood 35
A Basic Island1 voteshey dont make fun of my division
five oh tree 3 votesTrust the boards to defend a champion that's had a 53-55% soloq winrate for as long as most of us have been playing.
Yago2 votesJanna's like the most nerfed champion in League. She's overpowered, she always has been, and she always will be.
They would have to rework her completely out of her disengage niche or make her garbage at that role to affect her. Her ultimate and her Q are the entire reason she's impossible to balance. Her linear AoE knockup interupts dashes, can set up plays, has zoning potential / mind games, and a low cooldown, and her ultimate knocks away, potentially, an entire team, nearly a screen worth of distance, which also interrupts dashes, and can set up her Q. Not to mention, movement speed is an absurdly strong stat, and Janna gets that in spades.
Sugar Momma1 votesThey aren't impossible to balance. Make her Q have a 0.25-0.5 sec delay before you can recast it (so she doesn't have an instant AOE knockup). They could also bring back the short delay on her ult (it used to require a lot more skill to use).
kamikazephyr2 votesJanna has terrible mana sustain lol, and poking her shield IS a viable strategy (unless they aren't maxing E)
Sugar Momma1 votesJanna has not only the largest mana pool of the supports, but largest one in the game. Only Kassadin has a larger mana pool than her at lvl 18, and Janna has the largest at lvl 1. And her lvl 1 mana regen is equivalent to other supports who have the best starting mana regen (9 MP/5).
http://leagueoflegends.wikia.com/wiki/List_of_champions%27_mana
kamikazephyr2 votesIt's relative. Her mana usage is greater than that of Morgana, Lulu, Nami and Soraka
Janna's shield costs 110 mana at maximum level and howling gale costs 150. Maxed out W costs 80, and her ult is 100 at all levels. A full rotation of Janna's abilities at level 18 costs 440 mana, around 2/7th of her entire mana pool, which is fair and pretty much equal to other supports.
Jaygo412 votesSays who? Janna zones you by walking at you. If you turn and fight she shields herself and auto attacks you. Her shield, by itself, wins bot lane.
Her Q cost is negligent and howling gale is rarely used in lane
kamikazephyr1 votesWhat's "Says who?" referring to?
And if Janna shields herself, you have a 10 second window to win a trade with her ADC
Sugar Momma1 votesMost poking spells have a CD that is around or very close to 10 seconds.
Another minor nerf I thought would be reasonable is upping her shield CD to 12 seconds.
Jaygo411 votesAbout the mana usage. She uses very little mana if you know what you're doing and you constantly win ranged trades. Melee supports are especially bad rn because of gank vulnerability
Sogreth1 votesSays who? Janna zones you by walking at you. If you turn and fight she shields herself and auto attacks you. Her shield, by itself, wins bot lane.
Her Q cost is negligent and howling gale is rarely used in lane
BAHAHAA! You're bad then. If you're scared of a Janna because she shields herself. You don't deserve to play this game.
Maybe back when the AD was still active after the shield fell off, I would be slightly scared, but now? Rofl. Hit her with 2 AAs and the shield falls off. Unless she has like 40 starting AP.
Hochelaga2 votesHi Mommy 8)!
Sugar Momma1 votesHey girl <3 I'm loving your 
btw
Sogreth1 votesOh yeah, let's just nerf Janna...AGAIN.
Sugar Momma4 votesShe's very strong, and there's never a bad time to pick her. The fact she is often paired with 
bot, who doesn't even use AD, says a lot.
Klavier2 votesI think she gets destroyed by poke comps.
RivetAce1 votesKayle top and Amumu jungle are in the same boat. Kayle's winrate is insane though.
King of Demons1 votesIf she gets nerfed to the point where she no longer has a 50+ winrate she'll be useless. She is good because she makes sure you keep your lead once you got it. Very safe, very effective.
Sugar Momma1 votesYes, but generally Riot doesn't like very safe, very effective champs. But for some reason 
and avoid meaningful nerfs for years.
kamikazephyr1 votesJanna was witch hunted out of the mid lane and considered top tier trash for the greater part of season 3 (since then, she hasn't been buffed in a considerable way). It wasn't until people saw pros still used her when they realized Janna is viable. Her numbers have already been nerfed. She's just a inheritly good support
RexSaur1 votesAs long as janna is not completely unviable shes going to have a positive win rate, because shes a very useful champ due to her kit so just having her on your team means you have a higher chance to win, and this is true with most supports (sona 53% win rate, nami too, etc).
So this is not a good reasoning to ask for a nerf, besides janna doesnt do too great vs the mages bot lane or poke champs.
Friendly Ram1 votesLower mana pool increase ap to ms ratio?