Three words: Armor On Hit.
Somehow, an offensive skill manages to be the most broken defensive skill in the game.
Get lucky enough to end up with Armor On Hit, Energy Shield Max and E-Shield Regen (usually starting as basic Swordsman for Attack Speed) and you're basically set for a long, long while.
Speed up to 100, buff eshield and eshield regen to like 70, then pour EVERYTHING into Armor On Hit.
Then watch as no matter how much that spider hits you, you keep gaining armor.
I love this game but oh my god Armor on Hit is broken.