@meddler: it does not matter how much damage or armor shred you put on garens spin

as long as its not enough that he can murder anyone in the game through repeated shields and sustain mechanics within 3 seconds, he will remain in a bad spot and get outdueled even by champions hes supposed to counter, in extended fights.

he will not win against a riven who lifesteals and shields in regular intervals to absorb his abilities. he will not win against tanks who shield off his spin and deal any form of % health damage. he will not win against certain adc who just drain tank him for 3 seconds or hit summoner heal once.

be it shield mechanics, lifesteal or spellvamp in champion kits, masteries, or items, you have made in combat sustain easily accessable for practically everyone in this game. most champions have some way to either regain health or entirely absorb damage and stay in a fight.

garen is a champion whos kit is built around dealing sustained damage. but the fact that his passive is restricted out of combat sustain forces him into a playstile that simply doesnt work for him.

he is too slow to play like a skirmisher and dive in and out of fights to regenerate health between trades. but if he cant end a fight within 3 seconds, he will get out sustained by his opponent and killed while his spin is on cooldown.

more important than adding a passive onto his spin that he can buy on what is pretty much THE core item for him, is a way to actually be able to take extended fights when he manages to get onto his opponent. and that means adding some form of in combat sustain to his kit like other juggernauts have available.