That's true, of course, in such cases transferring and adding information is essential. But even then, of course, integrated capabilities help to integrate data without additional tools that take over the EL of ETL. The transformation can then also take place in the target system. Here, of course, querying the source system directly would not help.... I think the Zero ETL term is flexible, whether it is analysis directly on the source system or data transfer without additional tools and transformation.