Why does CoolSculpting work faster for some people than others? (photos)

I had CoolSculpting done on my upper arms in January, so I am about 3 months out. I started noticing results by day 13. By 6 weeks I saw my maximum result, which I am thrilled with. I had CoolSculpting on my abdomen (upper, middle, and lower) 13 days ago today, and again, I have already noticed a definite change. Why do I see results so much faster than other people seem to? Is the speed at which the fat is eliminated by the body related to metabolism? I am just plain curious.