Of this abstraction. The values for getRadius() or getCircumference() in the above mentioned instance can be stored right, or they might be calculated, it would not issue on the caller; the setters may well or won't have Unintended effects; it will not matter to the caller. See @michael-puckett-ii 's respond https://propertyingurugram.in/godrej-properties-buys-15-acre-land-for-rs-403-crore-in-gurugram-from-microtek/