Wounds and Recovery
When you are injured you take some while to recover, not to mention such simple items as good food, warmth, and medical care. All thise costs money. After a session when you are wounded you must pay gold to recover. How much depends on how badly you were wounded.
You do not have to return yourself to unwounded after a fight (though its a good idea!) and may fight while still wounded. If you do not have enough money to fully heal you may have to remain wounded. If you are reduced to 0 Health and have no money at all then you are out of it for good (unless some kind Knight gives you money) and must retire a broken man to your country estates.