( saying ) to destroy sth that would make you rich, successful, etc.
KILL THE GOOSE THAT LAYS THE GOLDEN EGG / EGGS
Meaning of KILL THE GOOSE THAT LAYS THE GOLDEN EGG / EGGS in English
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005