Sunday 20 June 2010

BI Requirements Should Be Challenged and Discussed not just Gathered

There are many resources remonstrating with the IT community on the importance of gathering requirements. Failing to gather requirements, they warn, will lead to a poor solution delivered late and over budget. This is largely inarguable.

However, I would warn that simply 'gathering' requirement is as big a risk. Fred Brooks, author of 'The Mytical Man Month' once said that 'the hardest part of building a software system is deciding what to build'. And deciding what to build is a two way process rather than the act of listening, nodding and documenting that we all too often see in Business Intelligence projects.

From time to time, I hear someone cry foul on this assertion. They argue that it seems like the tail is wagging the dog or that the business cannot compromise on the requirement. I usually point out that simply building what the user asked for doesn't happen in any other field of engineering. Architects advise on the cost of materials when planning a major new office building, City officials take advice on the best possible location for a bridge and environmental consultants are actively engaged in deciding exactly if and what should be built in any major civil engineering project.

And this is exactly how we should approach business analytic requirements. As a two-way exploration of what is required, possible solutions and the implications of each. Incidentally, this is particularly difficult to do if business users are asked to gather and document their own requirements without input from their implementation team.

An example of why this is important is rooted in the fact that many BI technologies (including IBM Cognos) are tools not programming languages. They have been built around a model to increase productivity. That is, if you understand and work with the assumptions behind the model reports, dashboards and other BI application objects can be built very quickly. Bend the model and development times increase. Attempting to work completely around the model may result in greatly reduced productivity and therefore vastly increased development time.

So be wary of treating 'gathering' and 'analysis' as distinct and separate steps. Instead, the process should be an iterative collaboration between users and engineers. Requirements should be understood but so should the implications from a systems perspective. The resulting solution will almost undoubtedly be a better fit and it will significantly increase the chance of it being delivered on time, at the right cost and with an increased understanding between those that need the systems and those that build them.

"We fail more often because we solve the wrong problem than because we get the wrong solution to the right problem", Russell Ackoff, 1974