If you live long enough, you'll make mistakes

"If you live long enough, you'll make mistakes. But if you
learn from them, you'll be a better person. It's how you
handle adversity, not how it affects you. The main thing is
never quit, never quit, never quit."

-- Bill Clinton

Take your mistakes positively, make them as source of strength. Don't quit when you feel like you can't take it. Insist and resist. 

Assuming that you're about to achieved something but you feel like quitting. How should you manage it?

You don't need anybody to tell you who you are or what you are

"You don't need anybody to tell you who you are or what you
are. You are what you are!"

-- John Lennon

Have courage to tell about yourself, don't feel ashamed. Remember that you're what you are and no one else is like you.

How proud you are about yourself? 

You must never feel badly about making mistakes

"You must never feel badly about making mistakes," explained
Reason quietly, "as long as you take the trouble to learn from
them. For you often learn more by being wrong for the right
reasons than you do by being right for the wrong reasons."

-- Norton Juster, The Phantom Tollbooth

As part of improvement, in doing better things you will always encounter mistakes that becomes a measures or guide to get things done better.

Can you improve something without mistakes? 

Face your deficiencies and acknowledge them

"Face your deficiencies and acknowledge them; but do not let
them master you. Let them teach you patience, sweetness,
insight. When we do the best we can, we never know what
miracle is wrought in our life, or in the life of another."

-- Helen Keller

Our weaknesses are normal, but don't let it direct us. Use them in a way that could make us different from what is expected.

Is it possible to change and improve the original you?

If you can't change your fate

"If you can't change your fate, change your attitude."

-- Amy Tan

They say that our life is directed, but we can do more things to improve and change its course of destiny.

Do you believe that your attitude determines your fate?

It takes generosity to discover the whole through others

"It takes generosity to discover the whole through others. If
you realize you are only a violin, you can open yourself up to
the world by playing your role in the concert."

-- Jacques Yves Cousteau

The small talent or skill we have can be used to let the world know about us through sharing.

Can you improve without participation?