Thin Provisioning is better for business. It helps you save expensive SAN storage space, and it is one of the most prominent emerging storage technologies that make the best use of Storage Virtualization - a rather mature technology.
In today's heterogeneous multi-vendor storage environment, organizations increasingly seek ways to exploit their available storage resources to the fullest. Data intensive applications in HA environment, increasing customer expectations to get highest returns on their storage investments, stringent IT/Storage budgets - there are multiple factors that advocate the significance of thin provisioning in today's storage economics.
It is more important when your data storage crosses limits of terabyte. You cannot afford to under-utilize expensive storage servers. Thin provisioning facilitates centralized storage utilization monitoring and simplifies capacity planning. It also simplifies storage provisioning and reduces the operating expenses over time.