‘What comes first business case or requirements?’ I’ve heard this question asked a number of times. My personal view is that it is very important to develop business requirements before or alongside business case development.
The impact of business requirements on a business case
Write a business case without requirements and it is unlikely to focus on the business need. Why? Because you have no basis to formulate your business case. Requirements help solidify the problem or opportunity statement in a business case.
Developing Requirements and the Business Case at the same time leads to a stronger business case. Requirements support the definition of the problem statement. Cost estimates are easier to pull together. Available options will more easily be visible.
When business requirements aren’t developed up front the problem statement is unclear, and the estimates and options within the business case aren’t well defined.
Business requirements and business case go hand in hand
The one benefit of having a Business Analyst working with you early on at the inception stage of the project (it is really pre-project), is that they have the ability to work with the business to define the business requirements as part of the work involved in developing the business case.
By developing business requirements early you also have a clearer picture of the change impacts and what this will mean for the business. Change Management funding and resources can be fully included in the business case. An area overlooked often in business case development is change impact. To the detriment of the business and a successful project outcome.
I, therefore, suggest that business requirements run a pretty close first to developing your business case. If you do them side by side you ultimately end up with better outcomes for both documents, your business case and your requirements, and then ultimately the project that ensues.
Problems caused by not developing them together
Develop your business requirements too late after writing the business case and you will find that there is sure to be a mismatch between what has been requested and agreed in the business case vs the desired business outcomes. This will show up in the options that are proposed. It will also become evident with your financial costings and timeline.
The one thing that I can tell for sure of a failing project is that the business requirements have not been developed at the same time as the business case. Why? The project scope is so far off what was originally defined in the Business Case. It is not really evident they are one and the same.
Develop your Business Case and Business Requirements together. The true business needs will be understood. This will lead to a business case for a project that will deliver the desired change for the business.