Why do I have to disable then enable this script to work?

This script is fully functional, but for whatever reason it doesn't work unless I disable it then enable it. If this matters, it is inside the StarterGui.

Colors={script.b1,script.b2,script.b3,script.b4}
Frame={script.Parent.a1,script.Parent.a2,script.Parent.a3}
Sequence={1,2,3,4,3,2}
    Frame[1].BackgroundColor3=Colors[Sequence[1]].Value 
    Frame[2].BackgroundColor3=Colors[Sequence[1]].Value
    Frame[3].BackgroundColor3=Colors[Sequence[1]].Value
    wait(.01)
while true do
    local w=0.07
    Frame[1].BackgroundColor3=Colors[Sequence[5]].Value
    Frame[2].BackgroundColor3=Colors[Sequence[2]].Value
    wait(w)
    Frame[1].BackgroundColor3=Colors[Sequence[6]].Value
    Frame[2].BackgroundColor3=Colors[Sequence[3]].Value
    wait(w)
    Frame[1].BackgroundColor3=Colors[Sequence[1]].Value
    Frame[2].BackgroundColor3=Colors[Sequence[4]].Value
    wait(w)
    Frame[2].BackgroundColor3=Colors[Sequence[5]].Value
    Frame[3].BackgroundColor3=Colors[Sequence[2]].Value
    wait(w)
    Frame[2].BackgroundColor3=Colors[Sequence[6]].Value
    Frame[3].BackgroundColor3=Colors[Sequence[3]].Value
    wait(w)
    Frame[2].BackgroundColor3=Colors[Sequence[1]].Value
    Frame[3].BackgroundColor3=Colors[Sequence[4]].Value
    wait(w)
    Frame[3].BackgroundColor3=Colors[Sequence[5]].Value
    Frame[1].BackgroundColor3=Colors[Sequence[2]].Value
    wait(w)
    Frame[3].BackgroundColor3=Colors[Sequence[6]].Value
    Frame[1].BackgroundColor3=Colors[Sequence[3]].Value
    wait(w)
    Frame[3].BackgroundColor3=Colors[Sequence[1]].Value
    Frame[1].BackgroundColor3=Colors[Sequence[4]].Value
    wait(w)
    end