Problems of Protocol Intercompatibility
Every piece of software has a limited set of supported communication protocols. Even if an application supports multiple protocols, it “prefers” one of them to others in the list, typically having performance issues with using the least preferred. Getting a few different applications to work together may prove a real challenge. When it comes to virtualization, this happens a lot with storage and consumers. They use different, often mutually incompatible uplink protocols. For example, Microsoft Hyper-V "prefers" SMB3, also working with iSCSI with certain issues and not working with NFS at all, while VMware vSphere works with NFS and iSCSI, but not SMB3, so finding a storage for both environments simultaneously can be tricky.
Some software, like VMware vSAN, has its own proprietary protocol, making it even more of a challenge to achieve compatibility. Specialized solutions that allow multiprotocol communication, such as additional "gateway" layers, require skills and money, also being a bottleneck in performance, because all the data has to go through them.
Products from different vendors support incompatible protocols