There are many advantages to having "standard" process models. One is that individuals within the organization can more easily and clearly communicate with each other about the various processes they are working to improve. More important to understand is that having a "standard" process model does not and should not mean "one" model. It's critical for analyst to understand how swim lanes, BPMN, EPC, UML, and other notations help in analyzing the "real" issues and problems in any kind of process whether it's a technical, people or combined process.
Many people might be surprised to learn that not all processes can or should be modeled as a "flow", that no one technique tells us everything we need to know about a process, and that "system flows" and "process flows" are two very different things.