The cloud computing model — especially the public cloud — is unsuited to many business applications and is likely to remain so for many years due to fundamental limitations in architecture and design. Enterprises that move their IT to the cloud are likely to encounter challenges such as security, interoperability, and limits on their ability to tailor their ERP to their business processes. The cloud can be a revolutionary technology, especially for small startups, but the benefits wane for larger enterprises with more complex IT needs. Utility computing still cannot match the "plug-and-play" simplicity of electricity. On the other hand, private clouds offer the benefits like scale and virtualization with fewer drawbacks.