Why the netcode issue exists, and why it cannot be fixed.

[Pikachew]

Even at light speed + infinitely fast server/client you'd expect a game like WoW to have same issues as FF14 about 3% of the time (0.01s lag versus 0.3s lag) if it ran on the same model, and nobody would consider WoW's PvP as acceptable if an ability like Ice Block failed with 3% the frequency compared to say Hallowed Ground failing in FF14 (which can be quite often). Note that here failure means you used the ability, and was charged the CD, but it did not activate.

People need to stop using Hallowed Ground as an example. The skill doesn't fail because of the .3 second lag it fails because it has a casting animation. Which is very much warranted considering how good the ability is.

[Astarica]

People need to stop using Hallowed Ground as an example. The skill doesn't fail because of the .3 second lag it fails because it has a casting animation. Which is very much warranted considering how good the ability is.

You can find logs that looks like:
1. You use potion for 100 HP
2. Mob hits you for 50 HP
3. You die

Is there a drinking animation on potions too? The 'casting animation' is the exact same problem. It comes from the fact that something has occured on your client (you drink a potion or used a skill) that is not yet acknowledged by the server. There's no grand design trying to balance certain skills with a hidden lag. You can use something as a weak as a regular potion and you'll still find that you don't get the 100 HP at the instant you think you do.