Originally Posted by FaerellG
Certainly, gold is a constraining factor, but the primary issue is timing and benefit. When building At-mogs, you build warmogs first. Warmogs is pure defense. Raw HP and HP regen, and it is costly. So you dump your first 3k gold into Warmogs and you get no offense or resistances (which offer superior protection). You don't get any offense until you finish your Atma's.
I would like to point out a few things. First of all, early game Health is actually more effective defensively than armor or MR, especially against multiple damage types. This is because your health starts out fairly low (500ish) but goes up to 2000ish for free by level 18. You dont get near as much gold-worth of armor or MR as you level so armor/MR is better later on.
If you have say 800 health and 40 armor/MR and you go B to buy stuff,
you have effective health of 800 x 1.4 = 1120.
a) buy Giant belt - +430 health. EHP of 1570 vs both dmg types.
b) buy cloth and chain(closest costwise to belt) - +58 armor. Now you have EHP of 800 x 1.98 = 1600ish vs physical, 1120 vs magical.
So bonus health is better early on (though not as helpful for your HP5/lifesteal). In any case, its not any worse. Having the high health endgame is still valuable, since any armor/MR you pick up gets multipled by the higher health.
Secondly, an early warmog/regrowth/etc gets you quite a bit of sustain which a Phage will not buy you. This might mean you don't need a Wriggles or other sustain item you might otherwise pick up, since you get an extra 15HP5 for super cheap that you will build into warmog.
A completed warmog adds 30-40HP5 which is pretty significant.
Third, the warmog is significantly more cost effective. 3k for 1270 health (and 1200g of regen), vs 3.3k for only 700 health, 800g of AD, and a snare. The main question here is: how valuable is that snare?
With a warmog you might still take a Phage before or after atma and go Triforce with it to get MS boost, more damage, and some snare. Some champs don't even need the snare all that badly.
Fourth, by midgame your champ will have a good 80AD plus 20 or more from runes/mastery = 100 AD. They also have 1 maxed out skill with pretty decent base damage already.
If you only have a Warmog, you should still be pretty decent in team fights if they break out. Even with 'no damage items' by then, most of your damage comes from your base values anyways.
I mean, a phage and giants belt means you have 18 extra AD. So...120AD instead of 100. Woopie?
Nothing forces you to complete the warmog ASAP either. its best so you can get it maxed out, but that isn't exactly difficult to do. It takes 100 minions, with champ kill/assist counting for 10.
So you can get giants belt, regrowth, then whatever else you want, then go back to complete warmog. You could even get the same belt,phage that was suggested which is fine if you really need the snare, then finish into Warmog instead of Frozen Mallet.