after shooting the sick dog,atticus will not allow Heck Tate to boast about his nickname ''One-shot Finch''.why?

Atticus is a humble man. He is, in every sense of the word, a gentleman. When Atticus shoots the dog, it is out of necessity. Both Jem and Scout love and respect their father but find him on the boring side. When he shoots the dog, the children are speechless. Heck Tate makes the complement but Atticus does not want the fuss. Boasting, even by someone else, is not in Atticus's nature. Guns are certainly not something that Atticus wants to be associated with. Still everyone is duly impressed.