Has to walk into vision range before killing
Has to scream and shout to the enemy team: "I'M COMING TO KILL YOU" until his ultimate dies off or he jumps onto the carry he was trying to hunt down, who is now huddled up against 4 of his teammates.
Has to right click out of his stealth and press his R button in a precise combo, extremely hard to pull off - don't you see? There's an overwhelming difference between the two.
Funny stuff aside though: I don't think it's Twitch, I think it's the fact that ADC's blow up way too quickly via: game is too snowbally. Seriously, do you know what DPS Stands for Rito? Damage-Per-Second.
So let's create a new category of marksman:
BPS - Burst Per Second

DPS - Damage Per Second

Now let's take a look at what champions seem to be problematic:
Isn't a problem, usually never a problem - receives less nerfs than most ADC's.
Isn't a problem - she's annoying as hell but isn't exactly an abuse case.
Isn't a problem - usually never a problem - receives less nerfs than most ADC's
Isn't a problem by himself - he was a problem when the meta was being forced to stay as it was when the worlds was going on.
Isn't a problem, usually never a problem - receives less nerfs than most ADC's.
Isn't a problem, usually never a problem - receives less nerfs than most ADC's.
Other than the fact that she can 100-10 you with 1 Q after 3-4 items - Isn't a problem, usually never a problem - receives less nerfs than most ADC's.
Problematic when he gets ahead - can completely wipe an entire team with an ultimate mid-late game - the only counterplay to his stealth currently is assuming where he is going to be and not being engaged on. If he didn't do so much damage in burst motions, it'd be okay but he does more than 1.5K Damage in seconds alone.
This bitch is way too fucking safe for being a 'risk taker.' That is all - she's actually pretty damn healthy compared to others.
Isn't a problem, usually never a problem - receives less nerfs than most ADC's.
Isn't a problem, usually never a problem - receives less nerfs than most ADC's.
Isn't a problem, usually never a problem - receives less nerfs than most ADC's. Trash.
Flex pick - can go mid, top, bot and I'm surprised not jungle yet. Has more burst than even a mage and with free poke, access to AD and AP items - he has pretty 'okay' dps and serves his role pretty well.
Gets 1 kill and steamrolls you the entire game, does losing 1/4 your HP after dying once sound fun to you - good, enjoy that after 1 single loss in the bottom lane.
A champion that's been named after a rioter who has been breaking items since his creation has refused to be nerfed throughout his characters existence - how strange. First it was this item - then the next, now it's Ezreal jungle and now he's 1 shotting people because this keystone says so - I'm sorry, why did Lulu mid and top get removed but the adc gets to enjoy being played in the midlane, the toplane, the jungle, the adc role - and with the new kleptomancy rune - I get to have an income on par to my adc's if I choose to go support? Why does this guy get to march his way everywhere?
Got dumpstered, when he was good - he was good.
He can't get 2 auto attacks out by the time the enemy adc just did 10 Billion damage to him and his team.
Cheese. That is all. Cheese.
R
Bursty DPS risk taker that has been a problem for quite a bit actually.
"Loses in lane" LOL K this bitch just needs to do a cartwheel with 3 items and he just nearly 1 shot your mid laner. Burst and DPS - sounds fun, right? Lets give this whore some stealth too, that sounds like fun. And some self peel. And some of this, and some of that - why not throw in some additional mobility creep too . . .?
Overall: DPS ADC's aren't the problem, it's the ADC's that aren't actually DPS's that are the problem. They're acting as a missing role that is the assassin role, and they have decimating damage that is not able to be dodged compared to champions that have abilities that can be dodged.