Because on the digital platform there is only ONE repeat ONE system/format that is recognised by APCO as truly meeting the mandate of interoperability. That is the Project 25 Standard. No matter who else is running an P-25 system, no matter what band, conventional or trunked, P-25 IS P-25. P-25 is NOT compatable with MotoTRBO, NexEDGE, OpenSKY, TETRA, and so on. The whole reason P-25 was developed was to get everyone on the same page so to speak. Now we may as well ALL speak twenty different languages with everyone wanting to be DIFFERENT from everyone else AGAIN! You run on unsecure, and ancient VHF Lo, she runs on TRBO, they run on NXDN.... But thats ok we will just patch, twist, sneak around and patch like we always used to... OK cool go ahead.... When a real disaster hits AGAIN.... I will talk to the real folks that want to help, and want my help on the P-25 system. Anyway that's a whole other topic from the valid point of getting VHF/UHF narrowband compliant...