Some of the worst employees a manager will ever deal with have a vocabulary problem. “No” and “maybe” don’t seem to be in their dictionary. Who are they? The “Yes” people — those who answer “How high?” every time the boss says “Jump!”

At first glance, they might seem like a manager’s dream employee — someone who doesn’t give you a hard time every time you make a request, who appears to treat your every wish as a command. Someone who never has a different — or better — idea. But is this what you really want?