One of the most notable drawbacks to the on-premises cloud is the cost of buying and maintaining IT infrastructure. Since you run the data center, you must acquire the proper hardware, servers, software, and storage systems to meet high-performance computing (HPC) requirements.
Public clouds or hosted environments operate at extremely large scales, leveraging vast economies of scale. They are able to provide the same services at lower operational costs than a smaller on-premises environment.
2. Disaster Recovery
If your system fails or a disaster occurs, you must have a backup for your data. In other cloud models, the cloud provider might handle recovery. With public clouds, you also have access to multiple geographic regions to distribute your risk of a disaster impacting your business.
As well as purchasing the equipment and software licenses, you'll need staff to run and maintain the infrastructure with an on-premises cloud.
Because you own the infrastructure with an on-premises cloud, you can keep your sensitive and proprietary data secure. With a hosted private cloud, though, you must rely on the cloud provider for security. This difference is particularly significant if you have intellectual property (IP) you want to protect.