Hud element ignores tweening?

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3

This script DOES work, but i dont know what makes it different from the other two.

local spinner = script.Parent
local tweenServive = game:GetService('TweenService')

local startatfive = 5

while true do
	local rotateBy = spinner.Rotation + startatfive
	local tweenSpin = tweenServive:Create(spinner, TweenInfo.new(1), {Rotation = rotateBy} )
	tweenSpin:Play()
	repeat task.wait() until tweenSpin.Completed
	startatfive += 0.1
end