its pretty much never correct to build that item, because someone on the enemy team always has some form of max health % damage.
even if the champions dont have it in their kits, its insanely easy to itemize into it.
health without resistances is worthless, and the passive on its own isnt worth enough to justify buying the item over other options.
warmogs needs to do more than it currently does.
BigFBear1 votesIn my opinion it's ok if there are 1 pure Health item when it make sense that it is pure health. Warmogs with his passive is such an item. It all says "the more health the better!" It's just fit.
But Frosthammer on the other hand... It makes 0 sense. The passive has nothing to do with health. And like you said. Health without defense is worthless. Frosthammer should be reworked into a Health/Armor item. Warmogs should stay the "one" Health only item.
Critmaster Garen1 votesIn my opinion it's ok if there are 1 pure Health item when it make sense that it is pure health. Warmogs with his passive is such an item. It all says "the more health the better!" It's just fit.
But Frosthammer on the other hand... It makes 0 sense. The passive has nothing to do with health. And like you said. Health without defense is worthless. Frosthammer should be reworked into a Health/Armor item. Warmogs should stay the "one" Health only item.
im not sure if you understood what i was trying to say.
there is no place for a pure health item in the game anymore. max health % damage is so prevalent, that buying warmogs is never the correct choice anymore.
any time you want to get more health to get a bit more tanky, it makes more sense to buy a resistance/health item, than it does to make warmogs.
even if youre not facing champions like 
or countless other champions who have health shredding in their kits, there are still items like 
easily available.
im not saying, that warmogs should be reworked into a health and resistance item, but it needs to provide more than just flat health and a passive that has very little priority.
this is another problem warmogs currently has. its passive is kindof nice, but compared to any other tank item, its not something thats good enough to make the item worthwile.
out of combat regeneration is never more important than 20% crit damage reduction, or 30% increased healing, or attack speed reduction and all the passives the health/resistance items provide.
Alzon1 votesYou don’t buy it so much for the health as you do for the regen... So what if you can tank 30% less damage than if you had bought Abyssal or FH, if you can do it multiple times before dying? Of course, this means you need to have some way to disengage. Somewhat of a niche item, but very strong within that niche.
Critmaster Garen1 votesYou don’t buy it so much for the health as you do for the regen... So what if you can tank 30% less damage than if you had bought Abyssal or FH, if you can do it multiple times before dying? Of course, this means you need to have some way to disengage. Somewhat of a niche item, but very strong within that niche.
the regen is never worth considering more than any of those items passives 
etc.
being able to survive fights is always first priority. warmogs currently adds a "nice" bonus that is actually not important compared to what other defensive items provide.
thats the problem. youre just looking at warmogs alone. you need to compare it to what other items provide in its place.
yes, being able to regenerate out of combat is a nice bonus. but is it better than taking 20% reduced damage from critical strikes or from ?
probably not. health/resistance items just generally provide more protection than warmogs.
Alzon1 votesThen Warmog’s is something you buy if you can already survive fights.
Critmaster Garen1 votesThen Warmog’s is something you buy if you can already survive fights.
when will that ever be?
when you can already survive fights, you either buy a damage item, or another health/resist item to make sure you dont ever die in fights, or you buy a utility defense item like 
that enables you to make plays.
the only purpose warmogs has, is to help you survive fights. but its not really good at that job compared to other available items.
no matter in which position you find yourself in, youll realize that there is always something more important, or something more useful than a warmogs.
thats why the item needs either a buff, or should get a different passive imo.
xDogMeatx1 votestanks dont exist vs brand hes the magic damage version of vaynes silver bolts.