I keep getting attempt to index nil with 'Parent'? Can somebody help me?

So I keep getting error like this!

10:28:21.632 - kit = script.Parent.Parent.Parent.Seat.Value.Parent.Parent
10:28:21.634 - system1 = kit.ONE
10:28:21.637 - system2 = kit.TWO
10:28:21.639 - ONE =  script.Parent.Animation.Value.ONE:WaitForChild('Motor')
10:28:21.641 - function onClicked()
10:28:21.643 - system1.A.ON:Play()
10:28:21.646 - system2.A.ON:Play()
10:28:21.648 - 
10:28:21.651 - ONE.MaxVelocity = ONE.MaxVelocity +:1: attempt to index nil with 'Parent'

And here is the full code!

kit = script.Parent.Parent.Parent.Seat.Value.Parent.Parent
system1 = kit.ONE
system2 = kit.TWO
ONE =  script.Parent.Animation.Value.ONE:WaitForChild('Motor')
function onClicked()
system1.A.ON:Play()
system2.A.ON:Play()

ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)                                        
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)	

ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025     
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
	
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025      
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
	
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025      
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
	
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025      
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
	
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025      
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
ONE.MaxVelocity = ONE.MaxVelocity + 0.0025
wait(1)
	
script.Parent.Confirm.BackgroundColor3 = Color3.new(0, 255, 0)
end

function onClicked2()
system1.A.OFF:Play()
system2.A.OFF:Play()
script.Parent.Confirm.BackgroundColor3 = Color3.new(255, 0, 0)
end

script.Parent.On.MouseButton1Down:connect(onClicked)
script.Parent.Off.MouseButton1Down:connect(onClicked2)

Can somebody please help also this is for a motor animation.