There are really a number of project lifecycle aspects that may facilitate business development.
You may have projects that are strictly for business development, such as constructing model units to facilitate sales. (unique work)
You may have projects where additional requirements are added to support future business development, in addition to the primary purpose of the project, as it is more cost-effective than a completely separate activity, e.g. incorporating new vendors or designs. (leveraging existing work)
You may have lessons learned from the project, which can be used in future projects influencing business development. (planning future work based on prior work)