(CareerBuilder.com) -- Courteous. Trusting. Good-natured. Cooperative. Tolerant.
These are the traits your mother told you -- repeatedly -- to embrace. "They'll make people like you." "You'll always have friends." "You'll go far."
Mom was wrong, at least as far as business success is concerned.
My colleagues and I studied the careers of more than 1,500 people over a 20-year period. Sorry, Mom, we found that being too nice won't boost you up the corporate ladder.
Our findings didn't just hint at it, either. The evidence was overwhelming: Being too nice can deter your career progress and muddle your effectiveness as a leader. The degree to which a person is trusting of others as well as likable (good-natured, cheerful, gentle) hurt his or her salary level and number of promotions.
How about nurturing, sympathetic and supportive? These qualities impede management potential. Agreeable? Research indicated it was negatively related to salary, occupational status, involvement in work and whether an individual stood out as a leader.
It's not all bad news. Being affable relates to job and life satisfaction, and people with that quality tend to engage in less counterproductive behavior -- vital in jobs requiring cooperation.
Why being nice hurts your career
So, why is it a problem for career success? One reason: People with this natural personality trait may be less likely to face confrontation or other difficulties at work.
I once worked with a hospital's vice president for marketing, a truly likable person. Successful in her early career, she started having trouble when she reached the vice president level. She faced significantly more power struggles and conflicts in situations where she needed to be firm or take a stand. Many times for harmony, she deferred to others. Over time, more assertive executives ended up simply ignoring her, making decisions without her. Frustrated, she eventually left the hospital.
A leader must be able to perform in ways challenging for someone who is hard-wired for cooperation. "Let's all get along" just doesn't work in the workplace.
To be a successful manager, you have to manage controversial issues as well as provide constructive (and not always positive) feedback. You'll have to make difficult decisions and help correct poor performance. Added to this, you'll have to be able to deal effectively with conflict and take less popular stands when needed -- challenging for those who want to be liked.
If you are that type of person, you may also be much less likely to stand up for yourself because you don't want to rock the boat, or be less assertive in asking for raises, promotions and career opportunities. Thus, others may take advantage of you or you might not get recognized for your accomplishments.
It has been proved that when "nice" leaders fail to manage conflicts, make hard decisions or deal with problem subordinates or areas, they are often accused of not providing strong leadership, lacking courage or just frankly needing to be tougher.
Being mean is not the answer
Does this mean you have to be mean? Absolutely not. Going to the other extreme and being abrasive, or a toxic co-worker or leader, is equally damaging to your career, as well as to others in the organization. Let me repeat: The evidence is overwhelming that being abrasive, disrespectful, abusive and mean will also derail a career.
Overall, being trusting, cooperative, forgiving and tolerant are all good things. But it's critical to recognize that any trait used in excess or inappropriately can become a weakness.
How do you change a personality trait? While traits generally drive a person's behavior, they don't necessarily dictate behavior. Your behaviors should be aligned with your work role and goals. Some of these behaviors may actually be counter to your natural predispositions, but most people want to help their organizations succeed.
Your next steps to success
First, you should determine what traits are preventing you from accomplishing goals or engaging in behaviors important to your job, or are creating negative perceptions of you as an employee and leader.
Next, be flexible in your personality and business styles. While the natural tendency of the vice president of marketing for the hospital was to be cooperative and flexible, she needed to speak up and take a firm stand on major decisions. However counter this was to her natural tendency, she needed to be versatile in her leadership style to handle new responsibilities.
Finding a balance
Can being too nice hurt your career? Yes. Can being too mean also kill your promotion chances? Yes.
I have facilitated many talent management reviews for major corporations. As individuals were reviewed by other senior executives, phrases such as "won't make the hard decisions"; "doesn't manage conflict"; "not sure he can lead us through the hard times"; "too much of a pushover"; "nice person but never gets anything done" ended up hurting individuals being considered for promotion.
Equally, phrases such as "gets results, but mows over people"; "can't manage a team"; "smart but has an abrasive interpersonal style"; "creates conflict"; "adversarial and doesn't solve problems in a productive fashion" ended up on the negative side of the review.
The keys are balance and versatility -- to apply the most appropriate behaviors as necessary for organizational goals. At times, it may be counter to your natural personality and outside your comfort zone. Keep this in mind: Remain authentic to who you are, but take the most appropriate actions needed for your leadership situation.
Dr. Christine Riordan is Dean of the University of Denver's Daniels College of Business.
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