What are the essential attributes of good software?

The essential attributes of good software are
Ans: Dependability: It should be secure, safe and reliable so: we can depend on it. In any case of system failure, it should not cause any case of physical or economic damage to the system.
Maintainability: It should be easily maintainable in any case of platform change or changing client’s needs.
Efficiency: It should give us perfect possible efficiency without over using required memory and processor cycles.
Usability: It should be user friendly and easy to interact with customers through an appropriate user interface and adequate documentation.