What you mean by Software Design Qualities ? Explain

WHAT YOU MEAN BY Software Design Qualities ? EXPLAIN ME

Software design quality means software design is according to required quality. In other words, it is fit for purpose. During design phase, we predict that whether software design is quality design. This prediction is based on certain parameters which include efficiency, compactness, reusability, and maintainability.

1. Efficiency is best use of resources such as processor time, memory, network bandwidth. 
2. Compactness is the property that a design can fit inside a human being's head. A good practical test for compactness is this: Does an experienced user normally need a manual? If not, then the design (or at least the subset of it that covers normal use) is compact. 
3. Reusability is whether system being developed can be re-used? 
4. Maintainability is how easy will it be to modify this system in the future? 

By viewing these four parameters, we can judge quality of a software design. Priority of these parameters varies from application to application but these are basic way to judge the quality of software.

For example, if we need to design an embedded system for the control of a nuclear reactor, we would probably require a system that is very efficient and maintainability would be of secondary concern. On the other hand, in case of an ordinary business system, we would prefer maintainability at primary basis because that application will be used for years in business.