There is a frustratingly common misconception that once a sweater starts pilling, it has reached the end of its life. You see those little fuzzy bobbles forming under the arms or along the sides where your bag rubs, and you assume the fabric is simply disintegrating. You might even think you bought a low-quality garment. I used to think the same thing. I’d look at a beautiful merino wool jumper from a shop like Marks & Spencer or John Lewis—retailers known for solid quality—and feel betrayed when the fuzz appeared after just three wears. But here is the reality: pilling…