(noun) An error; a blunder.
"I'm selfish, impatient and a little insecure. I make mistakes, I am out of control and at times hard to handle. But if you can't handle me at my worst, then you sure as hell don't deserve me at my best."
"Look at every mistake as an opportunity to learn and improve."
"Mistakes are acceptable if you learn from them; unacceptable if you don't."