The WiFi station connect sequence diagram does not have any "successful" ending.
It looks like a copy-paste error, because there are two consequent `SYSTEM_EVENT_STA_DISCONNECTED` events firing with nothing happening in between.
I think the original meaning was that the last event should be `SYSTEM_EVENT_STA_CONNECTED` to signify that if all goes well, that is the event that will be fired.
projects / esp-idf / commit