It makes no difference if the product is custom developed or COTS, it is essential to conduct a rigorous requirements process.
If the product is to be custom developed, the requirements will
be the foundation for the development contract. If the product is to be purchased, the
requirements will form the criteria against which products are to be judged. The process for
identifying, documenting and prioritizing requirements is covered in Skill Category 5. Often
the Requirements Development Process is concurrent with the Vendor Selection Process.
Great care must be taken with the Requirements if the vendor has already been selected. The
possibility exists that the vendor will shape the product to what is easy, cost effective or
efficient for them to provide rather than what the organization actually needs. This potential is
especially great when an organization has made a long term outsource commitment to a vendor.