All Passive Shields Are Broken

build is running 29% as runes (which I might change into full crit damage) running 12/18 with the storm raider keystone

I was using Tryndamere against Yasuo, I had 100% crit at 1188 damage per hit. He had a little under 2000 max health and was missing roughly 5%. He absorbed 4 attacks and killed me (didn't use my ult because I didn't think I'd need it). I hit him twice and took only about 400 health from him, he ult'd me and got his shield back, I hit him 2 more times and he had 700 health remaining when he killed me.

I used the same build against a Morde with , hit him 8 or 9 times times starting at 100 rage and didn't kill him.

Against Malzahar, I used (which was switched to late game)

Malzahar had I used my full combo, E > AA > Q > W > R > AA > R, the only thing it did was drop his shield and do roughly 15% - 25% of his actual health. After I saw his shield absorb my whole combo, I hit him with a W, waited for his shield to disperse completely, then did a E > AA > Q > R (and it killed him before my AA and the blades returned). Tried the same thing again, popped it with my W, but he backed off instead of casting, when I caught up to him and was close enough to press E, his shield was back up and he killed me. Then I realized it's up every 6 seconds.