iserith
Magic Wordsmith
And what I'm saying is that there are no "agreed upon failure conditions" in most cases. In my campaigns, failure could mean many things. The PC could die. They could become a prisoner kept alive for a prisoner exchange. They could become a prisoner only to be rescued later but lose all (or most of) their loot. They could become a slave in the underdark and we could start a new campaign either to rescue them or to lead a slave revolt. They could be dead but stuck between life and death with a chance to return if they succeed at some other task.
I don't have predetermined outcomes for any campaign contingencies, why would being defeated in combat be any different?
To be clear, I'm not saying any one play style is "wrong", just that if I find myself in a player death or TPK situation the cost of failure is going to be whatever I think will be most rewarding and fun for the group. For you that may mean your player dies.
Player death is undesirable. Character death is inevitable in a general sense when life-or-death stakes are in play.
When I talk about "agreed upon failure conditions," I'm talking about an understanding between the DM and players about what failure means in a given instance. I make that clear up front when describing the environment so the players can make an informed decision about how to proceed. In so many words, I'm going to tell them that the outcome for failure is death, capture, loss of equipment, escape for the villain, or whatever is appropriate to the challenge.