When talking about the levels of business processes, it is important to clearly state which relationship between the business processes is taken as basis for separating the business processes into different levels.
When business processes are combined into same hierarchy with other modeling concepts, it is important to clearly identify on which level which modeling concept resides.
People often talk about the levels of business processes, but based on the possible relationships between the business processes according to OMG BPMN and Open Group ArchiMate standards, there could be several different relationships of hierarchical nature, between the business processes, which all could form levels.
Letís look at the examples of two such relationships that allow forming of hierarchies (like specialization/generalization and containement):
There could be also other relationships between business processes, which allow formulation of levels, although in these cases the relationships themselves would allow forming of more complex networks, not only hierarchies, and therefore notion of levels gets even more unclear.
If talking about the levels of business processes it is important always clearly state which relationship between the business processes is taken as basis for the particular levels, otherwise the meaning of being in one or another level is lost.
If other modeling concepts (like groups/categories of the processes or activities or something else) are mixed into the hierarchy, then we cannot anymore talk about the levels of processes.
For example on following picture, only second level of hierarchy contains processes, therefore we cannot talk about first or third level processes:
Therefore, when business processes are combined into same hierarchy with other modeling concepts, it would be important to clearly identify on which level which modeling concept resides.