In the past, there was a time when I recorded in an excel sheet all my daily net wins or losses. I stopped it already and just now I realized how funny it was although useful. The main purpose at that time was to try earning daily from betting. I was doing casino games, especially dice, and of course my favorite sports betting. I did it for nearly a year. I can say, I mostly came up with a net win daily. And I can also see my grand total net profit and it was pretty decent.
Discipline and contentment are really the main keys IMO. We should always remember that we do not have to earn millions of dollars in order to be happy. This way, greed will not rule our minds.