axeplanation
One or more reasons for either chopping something or issuing a pink slip.
In da classic children's book, Lassie Come Home", da Duke of Rudling snortingly gives da Carraclough family an "axeplanation" of why he "had to sack" his animal-handler Hynes: "He was an utter nincompoop! Didn't know a dog from a ring-tailed filly!"