Professional life is all about selling yourself. Every day you need to sell yourself to others to make them believe that you can do the job they are asking of you.
To sell yourself you need to have an ego and you need to be confident. Ego shows you have pride in yourself. Confidence shows you have belief in yourself. If you don’t believe in yourself how will others?
However, confidence and ego are not the same as arrogance.
You are the best at what you do, you are the best person for the job, but there is no need to rub people’s noses in it!