Ego

When I say "I Can Do It", thats confidence
When I say "ONLY I can do it", thats ego

When I say "I am Right" and its based on my knowledge, thats confidence
When I say "I can't be wrong", thats ego

When I try to show that I'm on the right track, thats persistence (applicable only in professional life, in relationships, it doesn't matter who is right, what matters is who cares more for the relationship.)
When I try to prove that the other person is wrong, thats ego

On realising my mistake, if I accept it, thats humility
Even after realising my mistake, if I don't accept it, thats ego

When I respect a system and follow it, thats discipline
When I go against the system just for the sake of it, thats ego

When I don't hesitate to learn something new from my juniors, thats my thirst for knowledge
When I don't learn from someone just because that person is below me in ranks - Thats ego

When I say "I have done it, you too can do it", thats good leadership
When I say "I have done it, but you can't", thats ego

Confidence, persistence, humility, discipline, thirst for knowledge, leadership are what I need to move ahead.
Ego is the guaranteed first step to the endless road downhill.