I am 100% sure of what I am saying.
So I normally actively play as a miner in a 0.5 system and I can safely permatank the rats.
I can go to the kitchen, have lunch and stay 40 minutes there. No problemo I come back to game and the mining ship is there full of ore and shields at 50% or more.
Buuuuuuut… if I minimize game to watch some youtube video, 5 minutes later I maximize Eve Online and my mining ship is destroyed AGAIN, I am sick of this.
Maybe the shield recharge ratio is disabled when you minimize or whatever. But this makes no sense. I can permatank some rats when I am active but not when I minimize. Soooo clever.
I guess this is “working as intended” and a way of forcing us to play EVE Online as intended instead of minimizing it and watching a movie. But it is frustrating and I should warn you. I am sure this has happened to more people. Beware.
TL;DR dont minimize if you dont want to lose ships when mining.