Mostly to get some tips, but this one is quite universal. It's simply that you don't play all AD champs. I'm sure that a lot of people already knew how it would end.
There were other things I picked up on too like 2 tower pushing from IG, bot lane ganking mid, and pretty much everyone keeping up with the timer in cs.
Stars Shaper3 votesThere have been cases of purely AD comps winning. That happens though when you can get a consistent early advantage and capitalize on that, you need to playe xtremely aggressive and snowball your team to the point that every engage is favorable to you unless some huge mistakes happen.
This is why Fnatic lost.
AR URF1 votes[{quoted}](name=Stars Shaper,realm=EUW,application-id=3ErqAdtq,discussion-id=jk8vVQPm,comment-id=0000,timestamp=2018-11-05T10:01:53.104+0000)
There have been cases of purely AD comps winning. That happens though when you can get a consistent early advantage and capitalize on that, you need to playe xtremely aggressive and snowball your team to the point that every engage is favorable to you unless some huge mistakes happen.
This is why Fnatic lost.
I can see it working if maybe they had 
or something.
Sharpest glasses2 votesGo explain this to this board. That said, if ennemy run full squishies comp, you can go full AD.
Noor Sakata1 votesI mean , enemies had the Tankiest 2 tanks in the whole game , Ali and Sion , even if FNC Had AP , this might be even worse , Jhin can't do much against tanks like Ali and Sion , he isn't there for melting tanks , Top was lost and u know how and why but that being said , full ad teams might be bad in Pro Play since tanks are every match , BUT in solo no one plays tanks , since they are team reliant , they all play carries which is why full ad team is good , except for Sion and Ali of course