Make hearts go away one a certain amount of health is reached?

I'm currently trying to make hearts disappear when the player's health reaches zero, but nothing happens at all.

I first made it so that the max health is 3.

Script:

wait(1)
local P = game.Players.LocalPlayer
P.Character.Humanoid.MaxHealth = 3
P.Character.Humanoid.Health = 3

Next, I put three hearts and a local script into each of them. Each script makes the heart disappear when the health is at that number. But none of them work. I tried adding a while true loop, but that didn't work either.

Here is the local script I used that would remove every heart when the health reaches zero:

wait(1)
local P = game.Players.LocalPlayer

if P.Character.Humanoid.Health == 3 then
	script.Parent.Visible = true
end

if P.Character.Humanoid.Health == 2 then
	script.Parent.Visible = false
end

The other local scripts are similar, but they only remove the heart that they are in.