We all perceive the world according to our own reality. The experiences we have had in the past and the experiences we have today all create the perceptions that we hold about other people. Those perceptions influence our biases (and we all have biases), which in turn influence our behaviors.
Sometimes our biases are so ingrained that we don't even know they exist.
To be successful leaders and successful team members we have to become aware of our biases and how they influence our interactions with others in the workplace.