My bar goes up but not back down?

I've tried debugging this for a while, and it just not seems to be working the way it should be.

The bar (A TextLabel) goes all the way up (It's size becomes {1,0},{1,0}) but it won't come back down like it should.

There is NO output, do not ask for it. There is nothing being printed in the Output for this. Do not ask.

motion = "Up"
poweringup = true

repeat powersize = math.random(10,100)/100 until powersize ~= 1
redcolor = 1 - powersize
greencolor = powersize

while true do
	if poweringup == true then
		local powerbar = script.Parent:WaitForChild("TaskGUI"):WaitForChild("Frame"):WaitForChild("PowerFrame"):WaitForChild("PowerBar")
		if powerbar.Visible then
			powerbar.Size = UDim2.new(powersize, 0, 1, 0)
			powerbar.BackgroundColor3 = Color3.new(redcolor, greencolor, 0)
			if motion == "Up" and powersize < 1 then
				powersize = powersize + .025
				redcolor = 1 - powersize
				greencolor = powersize
			elseif motion == "Down" and powersize > 0 then
				powersize = powersize - .05
				redcolor = 1 - powersize
				greencolor = powersize
			elseif motion == "Up" and powersize == 1 then
				powersize = powersize - .05
				redcolor = 1 - powersize
				greencolor = powersize
				motion = "Down"
			elseif motion == "Down" and powersize == 0 then
				powersize = powersize + .05
				redcolor = 1 - powersize
				greencolor = powersize
				motion = "Up"
			end
		end
	end
	wait()
end