Why does this print nil even though the table isn't nil?

local UIS = game:GetService("UserInputService")
local Voted = {}
local player = game.Players.LocalPlayer.Name

function Update(Update)
	if Voted[player] then
		print("yep")
	else
		table.insert(Voted, player)
		print(Voted[player])
	end
end

UIS.InputBegan:Connect(function(Key)
	if Key.KeyCode == Enum.KeyCode.A then
		Update("Map1")
	elseif Key.KeyCode == Enum.KeyCode.B then
		Update("Map2")
	end
end)

On the update function, it keeps printing nil on the else statement, even when it has inserted it to the table.

You're looking for the players name in the table as a dictionary. When you table.insert, it adds a variable.

Try this:

local UIS = game:GetService("UserInputService")
local Voted = {}
local player = game.Players.LocalPlayer.Name

function Update(Update)
	local isOnTable = false

	for i,v in pairs(Voted) do
		if v == player then
			isOnTable = true
		end
	end

	if isOnTable == true then
		print("the players name is on the table")
	else
		table.insert(Voted, #v+1, player)
		print("player has now been added to the table")
	end
end

UIS.InputBegan:Connect(function(Key)
    if Key.KeyCode == Enum.KeyCode.A then
        Update("Map1")
    elseif Key.KeyCode == Enum.KeyCode.B then
        Update("Map2")
    end
end)