Why the time go past 0?

I made a complex script. But there was a problem. The timer went past 0. No errors on output.

Faulty script 1:

local replicated = game:GetService("ReplicatedStorage")
local player = game.Players.LocalPlayer

if replicated.Timer.Value == 0 and replicated.Intermission.Value == false then
    replicated.Timer.Value = 20
    replicated.Intermission.Value = true
elseif replicated.Timer.Value == 0 and replicated.Intermission.Value == true then
    replicated.Timer.Value = 3
    replicated.Intermission.Value = false
    replicated.Countdown.Value = true
elseif replicated.Timer.Value == 0 and replicated.Countdown.Value == true then
    replicated.Timer.Value = 121
    replicated.Intermission.Value = false
    replicated.Countdown.Value = false
end

while game.Players.NumPlayers <= 3 do
    if replicated.Timer.Value == 0 and replicated.Intermission.Value == true then
        local Blue = {}
        local Yellow = {}
        local Green = {}
        if player.leaderstats.Team == "Blue" then
            table.insert(Blue, player.Character)
        elseif player.leaderstats.Team == "Yellow" then
            table.insert(Yellow, player.Character)
        elseif player.leaderstats.Team == "Green" then
            table.insert(Green, player.Character)
        end
        local chosenplayer1 = Blue [math.random(1, #Blue)]:MoveTo(game.Workspace.R62_Trk1.Model.VehicleSeat)
        local chosenplayer2 = Yellow [math.random(1, #Yellow)]:MoveTo(game.Workspace.R62_Trk2.Model.VehicleSeat)
        local chosenplayer3 = Green [math.random(1, #Green)]:MoveTo(game.Workspace.R62_Trk3.Model.VehicleSeat)
        wait(120)
    end
end

Faulty script 2:

while true do
    repeat
        wait(1)
        replicated.Timer.Value = replicated.Timer.Value - 1
    wait() 
    until replicated.Timer.Value == 0 or game.Players.NumPlayers <= 3 and replicated.Timer.Value == 0
end