When does “self-confidence” become too much?

In case of overconfidence which result a disaster.

Self confidence comes with depth of knowledge, exposure, experience, willingness and desire to learn more from others.

Over confidence leads to arrogance and is a trait of people who are glib, shallow in knowledge, does not have space for better ideas / suggestions from others, are poor listener and thus poor learners.

When you don't except any suggestions from others and you think you are always right. 

When you think you're the best of the best.

When it replaces implementing processes which created it.

When you think and act that you are always right and believe that you are better than to anyone.  And you think and act that you are good in all aspects, that is too much confidence. you may not notice that you became arrogance and possess too much pride.

when it makes one encroach into others' area of influence or work.

First of self confidence constitutes self efficacy and self esteem. And when it become too much or successful:

1. Doing what you believe to be right, even if others criticize.

2. Willing to take risk, even extra miles go ahead.

3. Admitting mistakes and learning from others.

4. Wehn others are waiting to congratulate on your accomplishment.

5. Accepting compliments graciously "Thanks for the work done on the particular project or prospectus"

For any task, when you say i can do  - it is confidence

For any task, when you say i only can do it  - it is over confidence

Human brain is a magical pot and we will try to fill it with knowledge by way of learning new things and you gain confidence in turn to do it better.

The magic in this is thie pot will always have some more empty space to fill new knowledge till that time you are confident.

When this pot becomes full that means you cannot add any new knowledge to it, it happens when you become over confident.

And life becomes stagnent and anything which becomes stagnent it is bound to become redundent and useless and some times it is harmful also.

The most funny example is when the cat closes its eyes and start drinking milk and thinks that no one is seeing or observing it. 

Good Day!!!

Learning, Experience, Practice and results gives you "Self-Confidence" 

Any "Distraction" in learning leads to "Over-Confidence"

False Appreciation (unnecessary) on average results leads to "over-Confidence"

Offensive display of "Self-Confidence" "leads to Arrogance"

Leading with "Arrognace" is a disaster for "Oneself" adn for associates as well

THE SADEST EXAMPLE WAS MY "OWNSELF" But i defeated this devil years ago by truly believing in what my religion taught me. 

Self confidece is a belief that you can learn to correct your imperfection and a feeling that you are okay being imperfect, its just that you need to tweak yourself a bit to serve better and be a productive professional. However, not realizing it, results in both lack of confidence and arrogance. Arrogance itself is nothing but an expression of defying your inablity to learn and be better. That's when it becomes harmful. For Example, if you get offended when someone corrects you or suggests you, means you are arrogant and have an ego problem.

when you stop working as a team and this would lead to a disaster ....