If we start to look at the role of the developer; he or she should write the underlying code for the application, and not have to focus on the actual business rules that should be implemented in the system, i.e., should a certain threshold be above or below a certain level, and what should the level be? He should just know that based on this and that data that comes from these and those sources some rules should be applied and then this and that should happen. He should not have to care about exactly what the rules are, how many they are, what thresholds that should be set etc. These things should be left to the business analyst.
The business analyst should on the other hand not have to worry about how to get the data etc, he should just work on the business rules and set the right thresholds that should trigger certain things, for example a discount should be applied for certain customers, but not for others. He should just decide which customers the discount should be applied for and when it should be applied.
Now, don't get me wrong here, I firmly believe that this distinction is good, but I do not believe that it is enough, here are some reasons why:
- The tools requires the business user to be aware of technical issue that he or should not have to be aware of.
- I have not yet seen a tool that is easy enough for a business user to use.
There are further points on my list, but I will stick with these two for the rest of the discussion. This is not just only for our product in this area; this also goes for our competitors.
Normally the rules are stored in a repository, this requires from the end user to be aware of the location, how to open it, how to navigate to right screen, how to alter the rules and/or variables, how to add the syntax for new rules etc. I believe that any business analyst could learn these things, but is this really things that he/she should be focusing his time on? If I would run a business I would rather see them spend time on doing what they to best; not being a part time developer.
I would instead like to see that these things are handled by just a handful of people; I'll call them Business Rules Maintainers. These are the ones who should be working with the deeper maintenance of the rule repository; they could have a Business Analysts background but also needs to be aware of the technical parts of your rule product.
Now, the business analysts still needs to be there, and they need to be able to quickly adapt the rule system to the business, for example, one of you analysts suddenly discovers that a competitor has lowered the levels for being eligible for a discount and you think that this will impact your business if you do not do the same, so the analyst needs to quickly adjust your current discount levels in the system. At this point he should not have to open a full blown rule administration tool for this, he should just have to open a custom GUI in where he could quickly see what the current discount levels are and equally fast alter and save them.
So, to summarize, I believe that when you are designing the system, you should also start to think if your standard rule administration tool is easy enough to use for all your business analysts. If you come to this conclusion, fine. If not, start to think in terms how you could build a custom GUI for your business analysts that they could easy use to quickly tune your business to sudden changes in the environment, and make this GUI as simple as possible to use so that you won't have to turn your analysts into part time programmers. It might not be necessary to incorporate all your rules and threshold variable in this GUI, just the ones that are most critical to your business, and leave the rest to be maintained by the subset of your analysts that are the Business Rules Maintainers.
So to finalize the discussion, I think that when talking about developing and maintaining a rule based system, it is not enough to split the roles into developers and business analysts, I believe that at least one more role is necessary. It could also be that even further roles are necessary, but that is another discussion.