Notes on complex business “illogic” that makes business software so difficult

Even if a company unifies the technology for integration, they run into problems with differences in business process and conceptual dissonance with the

data. One division of the company may think a customer is someone with

whom it has a current agreement; another division also counts those that had a

contract but don’t any longer; another counts product sales but not service

sales. That may sound easy to sort out, but when you have hundreds of records

in which every field can have a subtly different meaning, the sheer size of the

problem becomes a challenge—even if the only person who knows what the

field really means is still with the company. (And, of course, all of this changes

without warning.) As a result, data has to be constantly read, munged, and

written in all sorts of different syntactic and semantic formats.

Then there’s the matter of what comes under the term “business logic.” I

find this a curious term because there are few things that are less logical than

business logic. When you build an operating system you strive to keep the

whole thing logical. But business rules are just given to you, and without major

political effort there’s nothing you can do to change them. You have to deal

with a haphazard array of strange conditions that often interact with each

other in surprising ways. Of course, they got that way for a reason: Some

salesman negotiated to have a certain yearly payment two days later than

usual because that fit with his customer’s accounting cycle and thus won a couple of million dollars in business. A few thousand of these one-off special cases

is what leads to the complex business “illogic” that makes business software so

difficult. In this situation you have to organize the business logic as effectively

as you can, because the only certain thing is that the logic will change over

time