Why didn't the employees in the Bronx Zoo remove the venom sack from this king cobra's mouth as soon as they?

many instances they milk the snakes for venom . its what they use in anti venom. but someone wasn't cautious enough and occasionally these things happen ! do we stop studying snakes and animals because of one accident ? i can almost promise the bronx zoo will step up safety measures and training as it will be a mandate from the insurance. this wont happen here again !! now maybe other zoos, but check history, this is a first. there is always a chance for human error, but learn from it !