You spend more money on soaps and detergents because hard water reduces their cleaning power. Raises your hot-water bills. Lime scale makes your hot-water heater less efficient because it insulates the water from the heating element. Clogs your pipes and plumbing fixtures. Lime scale builds up on the inner surface of plumbing, reducing its cross section.
Water flows more slowly.
Shower heads and sink aerators get clogged, often requiring replacement. Reduces the effectiveness of your clothes-washing soap. Your clothes aren't as soft and don't get as clean as they should. You buy and use more soap and detergent to get the results you want. Leaves spots on your glasses and dishes.