I believe generally that it's the spirits choice to move on once they have the help they need. For many reasons they are still here. Some ask for help, some don't know how to ask for help, some ask but not because they want it for "moving on reasons" but because it was the last thing they remember before they died and it's more residual. Ultimately, I think those of us who are sensitive/psychics/mediums/investigators are in fact gifted to help, period.