Soft goal


In connection with modeling languages and especially with goal-oriented modeling, a soft goal is an objective without clear-cut criteria. Soft goals can represent:
Non-functional requirements are global qualities of a software system, such as flexibility, maintainability, usability, and so forth. Such requirements are usually stated only informally; and they are often controversial. They are also often difficult to validate.

Why ''soft''?

Normally a goal is a very strict and clear logical criterion. It is satisfied when all sub-goals are satisfied. But in non-functional requirements you often need more loosely defined criteria, like satisficeable or unsatisficeable. The term satisficing was first coined by Herbert Simon. Soft goals are goals that do not have a clear-cut criterion for their satisfaction: they are satisficed when there is sufficient positive and little negative evidence for this claim, while they are unsatisficeable in the opposite case.

Relations between soft goals