Let's think now why we need to automate processes. One instant point that comes to my mind is to save time or hasten processes.
Actually, when we were working on the waterfall model, we had to iterate with development life cycle stages one by one, and modules were tightly coupled. Due to this, the development was a very long-term, complex process.
Now we move on to the agile development process, where each iteration between phases is very fast. It works in continuous integration (CI) and ...