This isn't a hate post against them, it's more confusion of the way Riot's been balancing them as of late.
When I started playing in S4, I remember that Caitlyn and Vayne both had set roles as ADC's. What I mean by this is Caitlyn was an early-mid game monster where she'd bully her opponents but would fall off hard later.
Vayne was the opposite, early game she had no way of easily killing someone but mid and late she became extremely strong.
So..What's going on anymore? Cait is oppressive in lane and oppressive until late game, Vayne has strength early and tons of strength late game.
I really wish they'd put them back into their set paths. It's really annoying that late game Cait can just one shot anyone and early game Vayne can deal extremely high damage.
Though Vayne has weakness early still, Caitlyn kinda doesn't have a point in the game where she's weakened at all. I think this needs adjustment since no champ should be built around all-game power. It should be reserved for specific parts of the game instead of all game