I wouldn't say "willingly inviting death" but I see the point you're making.
I'm reminded of an episode of M*A*S*H where a soldier was brain-dead due to too much shrapnel turning his head to swiss cheese. The doctors were waiting for his body to fully die (all other functions were still going, but slowly fading) because they needed to harvest some tissue to save someone else. The soldier's friend, recovering from his own injuries, was upset that they were just waiting like vultures to butcher his friend.
The priest asked him if his friend was the kind of guy who would jump on a grenade to save his buddies. The soldier responded that, yes, his dying friend would have done that without a second thought. "Well," the priest said, "that's what he's doing right now." He died back on the battlefield, the rest of his body just hasn't figured it out yet.
This guy is facing a similar decision, he just wants to make it himself while he can before someone else has to make it for him.