Nothing more dramatic than your favorite sweater suddenly coming out of the wash as a crop top! Wool clothing (merino, alpaca, mohair) is best washed as little as possible in the first place, and is best ventilated. Crocheted or knitted items are delicate so it is best to wash them by hand at a cold or lukewarm temperature, submerging them in water and definitely not soaking them. Still using the washing machine? Avoid horror stories by checking the washing instructions, use a small amount of wool detergent but no fabric softener and choose a low rpm (around 400). What about drying? Never wring out wool clothing or put it in the dryer. Rather, roll the garment in a towel to soak up excess water, stand on the towel to squeeze out extra water, and then let it dry flat on a flat surface with a towel underneath. Are there any lint (pilling) on your sweater? This is normal, you can easily remove these pellets with an unfuzzizer.