Success is problematic. As soon as you get something working well, you become nestled in a very comfortable plateau.
The tendency is to stay within the warm embrace of that plateau, savoring the sweet taste of success. But that, of course, is a trap.
Somehow, despite the siren call of successes safely achieved, you must row against the tide. Embrace the possibility of failure, be the agent of your own potential cataclysm.
Always, there must be risk. Without the possibility of failure, success is but a hollow victory.