While this looks like a lot of effort and many steps, all of this must be accomplished regardless of the size and scope of the project you are starting. Whether it is a new report request from an accounting department supervisor or a corporate directive to consolidate the multiple CRM and ERP systems into one global entity, the answers derived from your requirements planning are important to the successful completion of the project.
Now to answer the question, "How do you set business requirements as a percentage of the project time?...your timeline is done when you have it right.
Having it right means the information you obtain from requirements planning can be used to reduce, or at least, understand the project risks, satisfy the needs of the users’ and corporate goals, and not shut down the company’s operations to execute the project.
Looking at the trends for projects of all sizes, one finds that from 20 to 30 percent of the overall project time is spent in the requirements phase.
The lower end of the range is useful for projects that have few unknowns:
“I want to add a column to this report that is the average of the first two columns." May only need 15 to 20 percent of the time in requirements.
The more unknowns, the more time will be needed:
“We want to streamline our CRM and ERP operations in the US, Europe and South America to run on a single platform." Will probably take many resources and 30 to 35 percent of the project time to reach a level of comfort that the goals can be met without crippling the company.
The savvy project manager will begin by drafting a plan with 25 percent of the project time set aside for requirements and adjust as the discovery phase makes the project goals clearer.
Proper time and attention to requirements will benefit a project greatly. Insufficient time spent on requirements almost always increases the risk of schedule and budget issues, often deep into the project when it is most costly to recover.