Because opening a healthcare practice is one of the largest investments you will make, and that investment deserves professional proper management.  Ask yourself this:  why do you need a contractor?  Why do you need a lender?  Or a lawyer?  Or an architect?  The answer is because it is the proper way of doing things.  Having professionals in what they do helps the project become efficient.  Same applies for the Project Management position.  Without anyone od these professionals involved, you are the one that ends up doing the work.