Option 3 is used when a worker failed its job and you want to simply workers to quit. You can see below:
Option 5 is rarely used but the scenario is:
When a patch fails or hangs and workers are not in failed state, you use options 4 and 5 to mark workers as fail followed by killing of processes at OS manually if needed/if hung then use 5 to confirm manager that workers have quit.
You find in Page 225: