I think what Jangel means is still a teat or courage and bravery~ I mean the guild is representing the values of a bond beyond family, beyond friendship ~ For someone actually not willingly to fight one bit...would also mean that he would never fight for the guild~
I just think that they have to prove emotions and witts, so would someone with super high power who then immobilized you and kicks your ball, not be selected for the guild. 
Someone who is therefor kind but still faces the fight and looses with his head held high....well he would be choosen!