Me : Bizarre question. Depends upon so many things, some of which you can't anticipate. Why are you asking?
X : Rough hours to be successful?
Me : Successful in what? Define success? Define work? Also starting conditions.
X : How?
Me : A couple I know always grumble about being overworked and lack of success. They earn about $500k between them and define work to include "going to lunches", "beauty treatments" and "time in gym".
From the ashes of disaster grow the roses of success -
1) Spend time enabling, encouraging & supporting others. It can create positive feedback.
2) Be humble. Listen to others.