There is a lot of storage risk associated with a new application rollout. Without thin provisioning, storage to support this new application has to be bought, installed, powered and allocated. Thin provisioning reduces the storage costs associated with an application gone bad. In a thin provisioned world storage is only consumed by the application as it grows, so there is no need to purchase additional storage. If the application is wildly successful, free storage space is globally available and is automatically assigned to the growing application as needed.”]
Source: https://www.darkreading.com/database-security/thin-provisioning-reduces-the-cost-of-failure