This paper examines typical network cost behavior, as a physical, static and monolithic network evolves to one that is virtual, dynamic and optimally sliced. While this transformation eventually results in a more efficient network with significantly lower TCO, Bell Labs Consulting analysis found that the intermediate evolution stages will experience cost increases that result from transformation expenses, suboptimal manual slicing and operational inefficiencies. The key to achieving TCO reduction is through end-to-end automation that enables efficient network and service slicing and helps realize the full cost-saving potential of network virtualization.