Soft goal
In connection with modeling languages and especially with goal-oriented modeling, a soft goal is an objective without clear-cut criteria.[1] Soft goals can represent:
- Non-functional requirements
- Relations between non-functional requirements
Non-functional requirements (or quality attributes, qualities, or more colloquially "-ilities") 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 (i.e. management wants a secure system but staff desires user-friendliness). 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
- Decompostions
- AND
- OR
- Contributions
- Helps (+)
- Hurts (-)
- Makes (++)
- Breaks (--)
- Unknown
References
- ↑ S-Cube Knowledge Model: Soft Goals
Further reading
- Mylopoulos John, Chung Lawrence, Yu Eric: From Object-Oriented to Goal-Oriented Requirements Analysis]