Some laundry detergents do not produce as many suds in hard water, these are likely to be soap-based products and do not work as well in hard-water as detergent based products. (water-treatment.org.uk)

Hard water also contributes to inefficient and costly operation of water-using appliances. Heated hard water forms a scale of calcium and magnesium minerals that can contribute to the inefficient operation or failure of water-using appliances. (Wilkes University)

Clothes washed in hard water often look dingy and feel harsh and scratchy. (sciLinks)