When Is a Door Not a Door?
The Business Rule Difference
One of the interesting things about consulting with different organizations on business rules and publishing a journal2 on that subject is that a lot of really silly rules cross my desk. I think you might enjoy some of these, so I have included several small selections in Part III.
One reader recently forwarded a rule that raises some interesting questions. He observed that in his apartment building the doors to the stairwells all have signs on them that say, "Doors must be kept closed at all times." His question was, "Is a door you must never open really a door?" If the rule is followed religiously, he noted, the door might as well be considered part of the wall.
Before addressing that tongue-in-cheek question, let's do some analysis on this rule. I think we can safely assume that the rule as stated is actually a shorthand form. A more complete and accurate version might be, "You may use this door for entry and exit, but it must be closed behind you." If we wanted to be very complete, we might explain the basic motivation for the rule by adding, "This is a fire door."
Further analysis of this simple rule reveals some fundamental ideas of the business rule approach.
The rule was posted, that is, written down. Why? The answer lies in the motivation for the rule. Its purpose is to protect the inhabitants of the building against the dangers of fire. When a rule becomes important enough, it is always written down.
The rule was written in plain English. If the rule were difficult to understand or encoded in such a way that many of the inhabitants could not readily interpret it, the rule would not serve its purpose very well. A rule important enough to write down is worth writing plainly.
A procedure for this situation is not really needed. We could write one, of course, but in this case it would probably be trivial. ("Approach door; grasp doorknob with hand; twist doorknob in clockwise direction; pull/push carefully. . . .") Nonetheless, the rule is still crucial. Rules can exist independent of procedures.
This rulelike all rulesserves to shape behavior. The posting of the rule reminds inhabitants, staff, and others to close the door, and presumably they are therefore less likely to forget or perhaps even block the door open. The purpose of a rule is always to guide or influence behavior in desired ways.
The rule serves a purpose. It is neither frivolous nor arbitrary. Fire is a deadly risk, and all reasonable measures must be taken to protect against it. Business rules never arise in a vacuum; there are always identifiable and important business factors motivating them.
The rule was posted right where the action isthat is, where actual use of the door occurs. This proximity to the action helps ensure that people follow the rule as events actually unfold. The best way to ensure rules are followed is to get them right in front of people at the exact point where the guidance is relevant.
The rule is undoubtedly part of a larger body of regulatory fire code rules for buildings. Even though the rule might be posted thousands of times for enforcement purposes, these postings arise from a single source. This ensures consistency. If rules are important enough to be enforced, they are important enough to be single-sourced.
The body of fire codes was undoubtedly produced by experts experienced in the field and is backed by the political authority of the city or state. The regulations were not produced or mandated by an IT department! Business logic should always be specified directly by those people who have relevant knowledge.
Because of the importance of the regulations to the well-being of the community, any and all changes to them must be reviewed, approved, incorporated, and disseminated carefully. Because new dangers and liabilities can be discovered at any time, this process should be as streamlined and efficient as possible. On the other hand, over time some rules may become obsolete and even dangerous. The bottom line: Rules must be managed.
The Basic Principles of the Business Rule Approach
Rules should be written and made explicit.
Rules should be expressed in plain language.
Rules should exist independent of procedures and workflows.
Rules should build on facts, and facts should build on concepts as represented by terms.
Rules should guide or influence behavior in desired ways.
Rules should be motivated by identifiable and important business factors.
Rules should be accessible to authorized parties.
Rules should be single-sourced.
Rules should be specified directly by those people who have relevant knowledge.
Rules should be managed.
These commonsense observations represent basic principles of the business rule approach. Your business undoubtedly has literally hundreds or thousands of such rules guiding its various business processes. Yet in practice, these basic principles are seldom followed. In many organizations, the problem is so severe that the overall guidance process has just about broken down.
Can you do something about it? Yes! This book will guide you toward solutions.
Now back to that question, "Is a door you must never open really a door?" The answer is obviousyes, of course it is. A wall without a door will always just be a wall. If you need a door sometime in the future, you must remodel, and that means time and money (not to mention disruption for the inhabitants). If you have ever remodeled your home, you know exactly what I mean.
The wall with a door acts like just a wall until such time that the "must remain closed" rule is discontinued. Then, with relatively little delay, expense, or disruption, the wall can become a wall with a functional door.
Think of the business rule approach as a relatively inexpensive way to build potential doors for your business for all those many cases when they might one day be needed. That way you can avoid walling yourself off from best-fit solutions and quick-response opportunities. In a world of constant and accelerating change, adaptability is the name of the game. This is why your company should focus on business rules today!