Growing research on a variety of fronts shows that likable employees have more success on the job.

"Organizations have traditionally focused on competencies and thinking ability of their staff," Susan David, a Yale University psychologist, told USA Today. "There is growing recognition, however, that job effectiveness can be undone if an employee is not likable."

"Being proficient at job tasks is of little comfort to the organization if an employee alienates clients or other staff," David said.

While "The Likeability Factor" author Tim Sanders says likeable workers generally get bigger pay raises and promotions, "They Don't Teach Corporate in College" author Alexandra Levit says those who lack skills or are pushovers can be seen as a liability.

"Life is a popularity contest," Sanders said. "Likeability is the tiebreaker to almost anything."