Perseverence!

It's not that I'm so smart, it's just that I stay with problems longer.  ~Albert Einstein

Fall seven times, stand up eight.  ~Japanese Proverb

Saints are sinners who kept on going.  ~Robert Louis Stevenson

Success seems to be largely a matter of hanging on after others have let go.  ~William Feather

Pull yourself together and use what you have.  ~Betsy Cañas Garmon