Skin pilling is common and even expected at certain times. But there's only one exception where your skincare is not supposed to pill! If your serum or moisturizer is still pilling when you apply it on clean skin, overall well-maintained and regularly exfoliated skin, and if you don't layer anything on top or underneath it, that means the problem is the product and not something you do. In that case, the product is probably useless and you should get rid of it.