I guess it depends on the severity of the complication, other confounding factors, and a view of an individual woman and baby's unique circumstances. For example. a small hemorrhage that resolves with simple interventions, vs a torrential hemorrhage that results in the need for a blood transfusion or surgical intervention. How blood loss affects an individual woman would depend on factors unique to her (health status, iron levels, for example). Another example would be a 'simple' shoulder dystocia that resolves with a couple of interventions vs. one which results in a baby who is profoundly unwell and requires intubation and ventilation support. How well a baby would tolerate sticky shoulders or a dystocia would be dependent on factors such as whether there was a nuchal cord, whether the baby was doing well in the labour, if the baby was fighting infection or other complications. It isn't as simple as a list, really.
I am very comfortable at home, and part of the informed choice a woman has to make when planning a home birth is being at peace with the fact that many things will be just fine to handle at home, but there will be situations that will be better handled at the hospital and/or by specialists in *rare* circumstances. This is contrasted with the risks of some women being acutely uncomfortable in a hospital setting, the increased intervention rate, the increased infection rate, etc. Only the woman can decide for herself which risks and benefits are the most important to her when choosing place of birth.
Part of the relationship a woman might form with her care provider would form the basis, in an ideal world, of a relationship of trust of the midwives' skills and intuition and experience, and the midwife trusting and believing in the woman and normal birth, to make the recommendation to go to the hospital or to continue at home when things started to move away from ideal. Those decisions can't always been quantified or qualified when care providers don't blindly follow protocols and decision-trees, but individualize care to the woman and her unique circumstances.
Does that all make sense?