Three failures denote uncommon strength. A weakling has not enough grit to fail thrice.
Don't argue for other people's weaknesses. Don't argue for your own. When you make a mistake, admit it, correct it, and learn from it - immediately.
Robert Benchley has a style that is weak and lies down frequently to rest.
Our greatest weakness lies in giving up. The most certain way to succeed is always to try just one more time.
The weak can never forgive. Forgiveness is the attribute of the strong.
Never apologize, mister. It's a sign of weakness.
Positive feedback makes the strong grow stronger and the weak grow weaker.
Get to know your people. What they do well, what they enjoy doing, what their weaknesses and strengths are, and what they want and need to get from their job.