..as someone mentioned below my Citrine Chocolate eyeliner (lovely color by the way) didn't turn at all! When I tried the bottom cap just fell off. As far as I can see there's nothing on the inside just a hollow tube with no mechanism or anything. The actual eyeliner was probably too far for me to see. So... not sure how it's supposed to advance.

In any case this eyeliner was fairly smooth. The color was gorgeous and stayed on pretty well on my extremely oily lids. Assuming the liner advances somehow I'd highly recommend this product.