I wish to draw your attention to the word non-compulsory. The nature of flying is such that there is no exhaustive formula to cover all scenarios.
I am also not asking for scenarios covered by policies or procedures. Those need not judgement. There is no choice or judgement to be made for curfew, flight time limitation, aircraft defect, passenger's medical emergency etc. Do note I am talking about ramp turn back.
I sincerely believe that the scenarios that I have given are open to different judgement and decisions. For those who find it worthwhile to participate in a constructive discussion please give your views on the scenarios and preferably the accompanying reasons or considerations.
For those who think my scenario is straightforward, sorry to have wasted your time, please move on. I need judgement and views on the scenarios not of the question. Why not give it a try and see whether your common sense answer is universal?
You have started taxy:
1. Passenger clearly remembering leaving passport at the airport seating area.
2. Passenger clearly remembering leaving medicine for heart condition that may be critically needed in her check in luggage
3. Passenger received news of family member critically involved in accident and request for off-load.
Please don't worry, there is no right or wrong in any answers. General principle of thoughts can be voiced as views, universal exhaustive formula (if it ever exist) is not needed. If there are significant influencing factors you can list it as consideration.
ps: my junior colleague asked me how to 'fly' the aircraft in an abnormal situation. I answered aviate, navigate then attend to the problem with appropriate guidance, in that order. I would then apply the philosophy to illustrate to him the use and give him another scenario and asked him to apply the same methodology.