Forget past mistakes. Forget failures. Forget everything except what you're going to do now and do it.

We are what we repeatedly do. Excellence, then, is not an act, but a habit.

No man is a failure who enjoys life

If you make a mistake and do not correct it, this is called a mistake.

Grow strong, my comrade … that you may stand
Unshaken when I fall; that I may know
The shattered fragments of my song will come
At last to finer melody in you;
That I may tell my heart that you begin
Where passing I leave off, and fathom more.

He made a mistake, he got them mixed up.