‘Sagongi maneumyeon baega saneuro ganda.’ This literally translates as: If there are many captains, the boat goes to the mountain. This figuratively means that if many people give their opinion without a leader, working together will be difficult.
You can find the origin of the proverb in the book, Yeolja. In the Spring and Autumn Period in Chinese history (about 700s - 400s BC), there was a scholar named Yangja. One day, Yangja heard a loud sound while he was reading a book in his house. He wondered what happened outside, so he asked his servant to find out. His servant said the neighbor’s servant had to find some lost sheep. Yangja told his servant to help them. After some time, Yangja heard loud noises again. He went outside and found the servants arguing. They didn’t find the sheep because they were fighting about which of the many forked roads to take. Yangja sighed and said to himself that too many sailors (and no captain) can’t sail a boat.