Leaders should never surround themselves with people who only tell them what they want to hear. Even though it's tempting to exist in a positive feedback bubble, you need to fight this inclination and encourage independent thinking by others. If you are always the smartest person in the room and your opinions are largely left unchallenged then something is wrong. Sometimes the truth hurts, but it's better to deal with reality than ignore it. In addition, it's been proven that a group regularly makes better decisions than any one individual.
It takes a very confident and self-assured person to admit when they are wrong or don't know the answer. It can especially difficult when someone else points this out to us. Our defensive mechanisms tend to kick-in and we either ignore what's being said or lash out in response. It's amazing what happens to a person's body language when they feel threatened or challenged. I'd encourage you to pay close attention when this happens and force yourself to fight these natural reactions and intentionally listen to what's being said without judgment. Control your emotions and actually thank the person for their feedback. Focus on the issue at hand and the desired end result not just how you feel about what's being said.
Of course, everyone needs to feel safe to be vulnerable. You need to make sure your feedback circles have your best interest at heart. Some people just challenge things to challenge them and have their own personal insecurities for why the do this. Sadly it's much easier to criticize than create. Avoid these individuals at all costs. Misanthropes only ever end up sucking all the positive energy out of a room and fostering cynicism in others. However, there is nothing more powerful then a group of good people with positive intentions focused on common goals who are willing to be honest with one another. As with most things, it all start with the cultural tone set by the leader and his/her willingness to model the behavior they want to become part of their organizational environment.
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