Taking the time to learn from the outputs

Fred Giasson over Fred on Something has a good quotation from the book How to Win Friends and Influence people by Dale Carnegie which talks about reviewing output of tasks and projects and able to analysis what went wrong and what went well:

… “For years I have kept an engagement book showing all the appointments I have during the day. My family never makes any plans for me on Saturday night, for the family knows that I devote a part of each Saturday evening to illuminating process of self-examination and review and appraisal. After dinner I of by myself, open my engagement book, and think over all the interviews, discussions, and meetings that have taken place during the week. I ask myself:

“’What mistakes did I make that time?’
“’What did I do that was right – and in what way could I have improved my performance?’
“’What lessons can I learn from that experience?’
“’I often find that this weekly review makes me very unhappy. I am frequently astonished at my own blunders. Of courses, as the years have gone by, these blunders have become less frequent. Sometimes now I am inclined to pat myself on the back a little after one of these sessions. This system of self-analyses, self-education, continued year after yea, had done more for me than any other one think I have ever attempted.’
“It has helped me improve my ability to make decisions – and it has aided me enormously in all my contacts with people. I cannot recommend it too highly.” …

Taking the time to learn from the outputs of your GTD systems – [Fred On Something]
Related:
How to Win Friends & Influence People (Unabridged) – [Audible AudioBook]
How to Win Friends & Influence People – [Amazon Book]