Have you ever had a good idea and proceed to act on the idea and then run into resistance from your boss or co-worker because you didn't discuss it with them first?  Have you ever thought that the only reason these people were upset was because you thought of the idea first?  Have you ever noticed the more people are involved with a particular project or situation the less likely they are to complain? 

I used to be involved with coaching of youth soccer.  I used to watch many coaches that had problem parents try to keep them less and less involved with the team.  It almost never worked.  I did the opposite.  If I felt a parent was going to be a problem, I would give them a job to do for the team.  This didn't always work but in some cases it helped the situation greatly. 

People want to feel involved.  They want to have a say in the project or situation.  It gives them a feeling of control.  They are able see the big picture more clearly and understand the goals if they are involved.

Do you want a good example?  Since it's almost July 4^th, I will use the American Revolution.    

Many people believe that Taxes caused the American Revolution.  Although the taxes annoyed many of the American Colonists, I don't believe it was the cause of the Revolution.  If you do some research about the American Revolution, you will find that taxes were 5 times higher in 1698 than in 1773(The start of the American Revolution).  Furthermore in England, taxes were much higher than in the American Colonies.  What angered the American Colonies is that the taxes were imposed without consent from American's directly elected individuals.  So, grew the phrase "Taxation without Representation."

Again individuals want there opinion heard.  They want to feel involved with the out come.  They want a feeling of control.