What is most important: health, shield, or armour?

[Azrielus]

Self-explanatory really.

[Wahnwitzig]

Health + armor. Health doesn't help when your armor is very low.

[serker31]

All in all health is more effective, if you have means to restore it on demand. Especially when paired with armor.

[GunsForBucks]

I would say it depends on the frame.

A frame with low armor I wouldn't waste the armor mod in.. so if the armor is 50 or less I won't use steel fiber as a general rule.

A frame with over 100 base armor I make sure to put it in though as it makes a big difference.

[Spook]

health+armor offers much better scaling durability... for frames where it's an option. many frames' base armor is so low that modding for it isn't really going to be helpful.

just try to get hit less, mostly; stun everything or never hold still

[Wahnwitzig]

It also depends on your Warframe's abilities. Not every Warframe needs any health or armor at all.

[KnowTheFate]

Health is more helpful to focus on when playing certain warframes like nekros, nezha, and oberon. These warframes spawn health orbs like nobody's business so having a high amount of health with make you hard to kill as well as make it easy to make rage/hunter adrenaline builds that give you (basically) unlimited energy.

Armor's more useful for high base armor warframes like rhino, inaros, and atlas. Coupled with high health, these frames can have strong survivability.

Shields are rarely worth investing in as shield armor value is always pretty low and there's nothing you can do about that. At higher levels, shields (regardless of how much you have, barring overshields) gets broken through in just a few stray shots. It is only worth investing in shield values when playing warframes that can create overshields like trinity, mag, and harrow.

[No_Quarter]

in most cases it is:
1) health
2) armor
3) shields

decend health pool lets you survive procs and bad situations on higher levels.
armor adds to effective health, tho it's effectivness is determined by how much base armor you have, below 150-ish you should think about other means of survivability than armor.
lastly, some warframes have means to obtain huge shields and overshields (purple shield) which allows them to gain more benefit of added shield capacity. Tho procs still bypass shields so vs high levels health is still more relevant imo.

special cases are warframes with "stone skin" ability such as Rhino, warframes with damage reduction abilities - they all have special builds on how each variable is calculated so you should consult wiki. Like for Rhino and Nezha you only need armor and ability strength to gain max tank effect, other warframes with damage reduction usually have timer to it so ability strength plays the role on how much damage it reduces.

Quick Thinking mod is helpful for some real fragile warframes with huge energy pool, example being Ivara.

http://warframe.wikia.com/wiki/Armor
https://vignette.wikia.nocookie.net/warframe/images/a/a3/RDI.jpg/revision/latest?cb=20141112174415

best thing is to test stuff and see what works best for you, like I see most people using Redirection on Harrow for higher overshield but for me on higher levels I felt bit thin with such low health, even with 4000 shields procs still downed me so I went for health and I am still happy with 2850 overshield as I have means to maintain it and health lets me play more aggressive and gain more out of Harrow. And he is in my Top 3 favorite warframes.

[Cookie]

If Warframe's base armor is less than 100, consider health/shields.
-Shields are poor in scaling, but they are acceptable if you don't have source of healing.
And they are fantastic if you have warframe that reinforces shileds - more overshields.
-Health is great if you have decent armor and scales well.
-Armor alone alone won't do that well, except special cases like index rhino build.
-Combo - Health and Armor mods goes well with frames that prefers close relationships, such as inaros, excalibur.
P.S.
If your warfame swims in energy, use quck thinking. Will beat both options.

[Walrus-Sama]

Health, then Armor.

Sheilds are never useful. Even on frames that have ablities that enhance sheilds in some way. The only exception to this is using Arcane Aegis on frames with Damage Reduction ablities like Mesa, Gara, Nezha, etc. And even then, that's just using an Arcane with base sheilds.

On 90% of frames, just a Viatality is enough survivablity, and it only takes up one mod slot. On tank frames with good armor you'll want Vitlality and Steel Fiber.

[Donitsi]

Depends.

https://vignette.wikia.nocookie.net/warframe/images/a/a3/RDI.jpg/revision/latest?cb=20141112174415

If warframe has very low armor then Armor mods are useless. (Trinity for example has 15 armor so it doesn't matter how much more you give her, she will die just as fast.)

I ignore health mods for warframes who benefit more from +Shield and vise versa. If warframe has atleast 300 armor I will consider adding more armor.

[[88th] ColPresumptuous]

Health and Armor, Shields come back quickly health doesnt, and shields dont protect from toxin damage. Every bit of armor will make that health pool biggier.

BEst though is dont get damaged in the first place, most of my frames have only 300ish health and shields i just make sure i dont get damaged.

[✨Saint✨]

It really depends on the frames and mods.

Pretty obvious really.

[ClumsyMattress]

it al depends on the frame realy
for example a nidus and an inaros dont benefit from shield mods so health and armor are the important ones
a limbo doesnt realy need any of the three because of his abilities but shields would be a big plus for him if hes ever in trouble
wukong and his abilities make his requierments to be less armor and shield and more health so that he can be immortal
so just look at how the health shields and armor synergies with the frames abilities