too many cooks spoil the soup

too many cooks spoil the soup

If too many people try to control, influence, or work on something, the final product will be worse as a result. A: "We've got my boss, his boss, the assistant manager, a freelance consultant, and the head of IT all involved in this project, and it's turning into a complete disaster!" B: "Well, too many cooks spoil the soup, after all!"
See also: cook, many, soup, spoil