I think you are conflate not understanding context of how state needs to change vs we need to arbitrarily change state ad-hoc. The diagram isn't missing anythi

I think you are conflate not understanding context of how state needs to change vs we need to arbitrarily change state ad-hoc. The diagram isn't missing anything. It only describes the flows that it contains. This how I build all systems. It works. Nothing you've mentioned demonstrates a failure in this style of system design. I would suggest maybe there is a gap in your understanding?