Broth is thin soup of meat.
If we allow a cook to make the broth, he prepares it according to his knowledge and experience of making it. If it is not good he can rectify it and make it better next time. On the other hand, if too many cooks are allowed to make broth, the result can be disastrous. One will say one thing and another cook will say another thing totally contradictory. The result: a spoilt broth.
In much the same way, a task that requires one person should not be assigned to many. There is every chance that they may not get along well. The results will be bad. In addition it will not be possible to hold any particular person responsible for spoiling the task.
Any job needs a certain amount of discipline and coordination. This is possible only if the experts are limited in number. For instance take an office that has too many officers bossing over their subordinates. In such a case the quality of the job that the subordinates do suffers because of different and conflicting directions that are given by the bosses.
Likewise an army with too many generals will be unable to attack properly. A team with too many captains is most likely to lose.
There is a saying in Sanskrit, ‘Ati sarvatra varjayet‘. It means that too much is always bad. The phrase ‘too many cooks’ in the saying can refer to anything in excess.
The proverb advises moderation in everything. Therefore, only the required number of people, with their duties specified, should handle a job if that job is not to duffer in quality.