What are the characteristics of a well-written business rule?
I'm getting input from the department lead about the rules they follow to maintain compliance, but I'm not sure how to write them. What are the characteristics of a well-written business rule?
A well-written business rule helps everyone stay clear and on point about what's required. But business rules can easily become useless if they're too general, too complicated, too obscure, or just plain badly written. When it comes to composing business rules, learning the business helps immeasurably, because it helps you understand the logic behind the "rules" that govern the business processes and requirements.
Well-written business rules have some easily recognized characteristics.
A business rule generally includes three elements:
A term or concept
A fact about the term or concept
A rule that constrains behavior related to the fact or concept
For example, a business rule that begins with the term or concept "customer" might include a fact that connects it to other terms, such as "a customer places an order." The business rule might apply simple logic to the fact and concept, to guide decisions or constrain behavior. For example, "A customer who places an order must be at least 13 years of age."
To determine if a business rule is "good" or well written, ask these questions:
Can everyone understand it? Will everyone who reads the rule discern the same meaning, every time, to ensure that the rule is applied correctly?
Is it written in natural language, using clear, consistent terms? If the business rule contains terms unique to the business, project, or application, are those terms are defined in a project glossary, and do they mean the same thing every time?
Is it concise? A well-written business rule doesn't raise any of the following barriers to clarity: embedded "if then" statements, "when" statements, additional clarifying language, language to reinforce the message, or other extraneous terms or concepts that would better defined by their own business rules.
Can it be reused? Well-written business rules don't reference specific procedures or processes; therefore, they can be reused within the system, application, and even across the organization.
Does it specify "what"? Good business rules specify only what the rule is. They don't mention how the rule should be enforced, or the business value of the rule.
Does it use limiting terms? Good business rules should contain limiting terms such as "must" or "only," and should avoid vague, general terms that remove limitations, such as "can" or "should."
Does it specify "when"? A good business rule can either be inferred to be "always" true, or it should state specific times when it is or isn't true. There is no need to include words such as "always" or "never," but if the business rule is time-enclosed, the time reference needs to be included.