Why is the script becoming active but not making the GUI become visible?

So in Workspace, I have a folder named meep that contains an int value named Why. I also have a script that successfully changes the Why int value into 0 after 3 seconds. Thus, all the things that I'm printing are being printed in the output. However, the GUI does not show up even though the GUI's visible status is true. (It also becomes true when I tested it ). Also, I found out that the GUI does work correctly after resetting the character.

In Conclusion:

• int value gets changed -function gets activated -Gui becomes visible but the Gui does not appear on the screen
• Gui, however, does appear on the screen on the screen after resetting the character.

game.Workspace.meep.Why.Changed:Connect(function()
	wait(1)
	print("Hello")
if game.Workspace.meep.Why.Value == 0 then
	print("H3llo")
game.StarterGui.ScreenGui.Dave.Visible = true
else 
	game.StarterGui.ScreenGui.Dave.Visible = true
end
end)

The reason why your GUI only appears after resetting the character is that you're editing the StarterGui instead of the PlayerGui. StarterGui is essentially a container for all your GuiObjects that you want cloned into the player's PlayerGui each time they respawn. PlayerGui is the same thing, except it contains the GuiObject's that the player is CURRENTLY looking at. So if you wanted to make a change while the player is playing a game you should most of the time change the PlayerGui.

In order to access the PlayerGui, use a LocalScript and the following code:

local plr = game.Players.LocalPlayer
local plrGui = plr:WaitForChild("PlayerGui") --It's recommended to use WaitForChild because sometimes the player is added into the game after LocalScripts so it's just a safety precaution
local screenGui = plrGui:WaitForChild("ScreenGui") 

workspace.meep.Why.Changed:Connect(function()
	wait(1)
	print("Hello")
	if workspace.meep.Why.Value == 0 then
		print("H3llo")
		screenGui.Dave.Visible = true
	else
		screenGui.Dave.Visible = true
	end
end)

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