Before anyone upvotes this post, notice the OP never stated he did poorly in his game:
http://eune.op.gg/summoner/userName=LechintanTudor
Here is the Vayne:
http://eune.op.gg/summoner/userName=stefdmg
His last match against Vayne was where she was 41/9/9 - no wonder he lost. Thus, this is a vent post. He was 14/11/17. OP never built a single armor item either.
Vayne requires to be close to melee range - a range where CC and skillshots are very landable in a teamfight. With the amount of CC in a game, she's easy to catch out. She also is weak in coordinated teams and his team lacked this strongly compared to theirs.
Her Q doesn't burst by the way. There's actually no damage since it's additive damage which doesn't crit. Her tumble is mainly for kiting.
The sole purpose of Vayne is to be hard to catch - "Fighting against me is like boxing with shadows".
She just got a nerf BTW, so we'll need to see how she does first.
Assassins shouldn't kill tanks - they're not ADCs.
Assassins aren't meant for teamfighting - they're not ADCs. They're meant to get in and out of the chaos of teamfights - assassination. Picking those out of position.
Assassins need skillshots - they're not the marksmen role.
Assassins have delayed burst - many ADCs have the same amount of burst as Vayne and worse.
You're naming ADC traits and associating them solely to strengths of Vayne when all ADCs are like this. Twitch has a much higher DPS and burst potential than Vayne. Tristana offers the same kind of burst but with more safety. Notice, they are all good at teamfighting, killing tanks, and do not have delayed burst when they gain critical strike items.
Any assassin shouldn't be able to kill an ADC at any point of the game - else why should an ADC position/kite/receive peel.
This post seems composed more out of irritation than analytical suggestion.
If you're being bursted as an assassin, armor items are always there or damage reduction items. Just like ADCs are squishy, assassins are too due to the amount of damage their kits can create with just two items. An
easily offers no reaction time for an ADC to live through a single combo or an AA without significant armor. The same thing with assassins if they lack an armor item. If they cannot at least get randuins, GA, or defensive item to itemize against an ADC, why shouldn't you be punished.
TL;DR - Inability to defeat a very fed Vayne who has showcased amazing skill statistically with her carry that game made this OP tilt. Thus, he is using the Vayne hate bandwagon and coming to the boards. Also forgets to mention Vayne had peel and tanks defending her with a lot of CC. She also had a PD, mercurials, and 3 crit items against Zed.
So @OP, a quote for you:
"Oh no, assassins have to work to kill an adc. What a tragedy" -- Friend (Hidden)