I think it's because she doesn't depend on items that much, sure she does great with triforce, but even with one part of it you can do great.Plus last hitting with her is retardedly easy so money is never a problem, and her skills while not scaling that much are pretty strong early on.She's the perfect tanky DPS i think, having everything you need, her passive is great and combined with Merc treads you get 75% cc reduction in a teamfight, she has a nice dash that allows her to close with the enemy quite sneakily, while they hold back slightly so you don't dash their squish guts out you simply dash to a minion and then to them, since you know, nobody expects two dashes that fast.Hitten style while not being that important late game (except for the true damage, but that isn't that much) is insanely good at keeping you alive, a single minion wave will get you some half health without much problems.Her stun/slow is a great way to get out of trouble/stop others from getting away from it, it saved my ass quite a few times simply by stunning the bastard because he had more health than me, and again slowing him down so i can tear his face off.Ultimate is nice too, not only for chasing near dead people but quickly getting your health up after a big fight, simply find a minion wave and mash your R untill you are full, then you can push all you want without needing to go back.