I need some clarification

Why are some champs just inherently so tanky even if they shouldnt be? Last game I was LB mid vs Akali, I swear my early game QW poke was doing nothing to her. Is doran shield supposed to soak up that much dmg? Like I went in several times with QW and by the time I had distorted back, I had taken more dmg than her and she only hit me with a Q.

I even managed to kill her a couple times in lane but that didnt matter, by the time she got gunblade it was over, she ran over me easily.