spoil something that is good or something that one has by being greedy They sold part of their business but it was the most profitable part. I think that they have killed the goose that lays the golden egg.
KILL THE GOOSE THAT LAYS THE GOLDEN EGG
Meaning of KILL THE GOOSE THAT LAYS THE GOLDEN EGG in English
English idioms vocab. Словарь английских идиом и выражений. 2012