People who do too much tend to engage in a lot of internal negative self-talk. When we fall short of our goals, we state "I am a failure" - an absolute, self-fulfilling prophesy. In our minds, "I am a failure" implies 1) "I always fail," 2) "I have failed in the past," 3) "I will fail in the future," 4) I fail at everything I do, and 5) "the universe has a horror at my failure and will consequently punish and damn me for my failure for all eternity." It's difficult to change one's thinking from time-dependent and complete finality in our negative self-talk. People who do too much should catch themselves when engaging in negative self-talk and substitute positive affirmations that acknowledge a short-coming but not project it into the past or into the future or onto other activities. Something like, "Well, that didn't go as well as I hoped it would. It doesn't affect anything else I've accomplished. Next time, I'll make more realistic goals and succeed. Now, what's next?"