What is wrong with this script?

I asked this question before, and it worked :D. But when I tried it out, it went like out of order. Instead of starting from the first to the last, it did it backward. What is wrong with it?

local bin = script.Parent
local decal = bin.Decal
--The numbers(5.5) are how long to wait for each slide.
local MainSlides = {
["http://www.roblox.com/asset/?id=213163470"] = 15, 
["http://www.roblox.com/asset/?id=213486920"] = 3,
["http://www.roblox.com/asset/?id=157656296"] = 3,
["http://www.roblox.com/asset/?id=213486967"] = 3, 
["http://www.roblox.com/asset/?id=151111211"] = 3,
["http://www.roblox.com/asset/?id=213487020"] = 3
}

function runTable(tab)
    for i,v in pairs(tab) do
        decal.Texture = i
        wait(v)
    end
end

while wait() do
    runTable(MainSlides)
end