We can run the projects in a waterfall way according to the PMBOK® Guide or PRINCE2® approach or be more flexible, in an AGILE SCRUM PM way, but more important than this, we MUST have a WAY. That's why, everyone involved in a project should learn how to do it in an efficient manner, by learning PROJECT MANAGEMENT.
Looking through the "business eyes", BUSINESS ANALYSIS is the missing link between the project and its business clients.
In this context, the business analyst is entirely responsible for finding the optimal solution to the client problem or necessity.
Finding LEAN SIX SIGMA as a unique and logical merge between the faster "LEAN Management" which reduce the waste and increase the speed in providing products and services to the client, and the defects and variation tough killer, "SIX SIGMA", is the best you can do for raising your company.