“The President who understood best the need for organized disagreement was probably Franklin D. Roosevelt. Whenever anything of importance came up, he would take aside one of his aides and say to him, “I want you to work on this for me – but keep it a secret.” (This made sure, as Roosevelt knew perfectly well, that everybody in Washington heard about it immediately.) Then Roosevelt would take aside a few other men, known to differ from the first and would give them the same assignment, again “in the strictest confidence.” As a result, he could be reasonably certain that all important aspects of every matter were being thought through and presented to him. He could be certain that he would not become the prisoner of somebody’s preconceived conclusions.” – Peter Drucker, The Effective Executive

In this Ted Talk Andrew Millar discusses the importance of dissenters. People who like to challenge the process. They may come across as just trying to disagree, but they play an incredibly important role: these are the people who, sometimes, are able to help a group see a different point of view. 

If someone does not bring a different point of view to the table we will only have one: our own.