Soaps are less soluble in hard water why?

Grease and oil are non>polar and insoluble in water. These fatty acids are less soluble than the sodium or potassium salts and form a precipitate or soap dirt. Because of this, soaps are ineffective in acidic water. Also, soaps form insoluble salts in hard water, such as water containing magnesium, calcium, or iron.

Because they are solids. granted they have coating but since they are solids at first it's hard to dissolve