I’d say 8 or 9 times out of 10, you should be succeeding. Build momentum. Accumulate advantages. Feast on the feeling of success and let it feed your desire to do more.
But 1 or 2 times out of 10, you should be failing. Push yourself and reach beyond your current grasp. Force yourself to try uncomfortable things. Occasionally you will surprise yourself and the rest of the time you will learn.
Win enough to keep progressing. Lose enough to keep learning.”