if game.Players:FindFirstChild(players[i].Name) == nil then?

Why doesn't this work?

local players = script.Parent.Parent.Parent.PlayerNames:GetChildren()
local AllPlayersTeleported = false
local NumberOfPlayersTeleported = 0
for i = 1, #players do
		
			if game.Players:FindFirstChild(players[i].Name) == nil then
			
				NumberOfPlayersTeleported = NumberOfPlayersTeleported + 1
				table.remove(players, i)
				
			end
		end

Basically this line of code:

if game.Players:FindFirstChild(players[i].Name) == nil then

Which doesn't make sense because it returns the error that it is trying to index a nil value. I thought it's supposed to index a new value right? so why does the script break instead of return a nil value?

Common problem actually: table.remove shifts around the array values, so your for-loop becomes inaccurate. Say for two players: index 1 should work, but removal replaces value1 with value2. Index 2 is unexpectedly nil.

There are at least 4 solution to this but I reccomend the easy Lua one: avoid table.remove. It's a slow function anyway.

NumberOfPlayersTeleported = NumberOfPlayersTeleported + 1
players[i] = nil