What causes white spots on clothes when ironing?

White spots on clothes when ironing are often caused by a few factors, including the presence of hard water minerals that can deposit on fabrics, or residues from laundry detergents and fabric softeners that haven't been fully rinsed out. Additionally, overheating synthetic fabrics can lead to melting or scorching, resulting in discolored patches. Using a clean, dry iron and ensuring proper rinsing of clothes can help prevent these spots.