Without a doubt, Haman is one of the most evil people in the entire Bible. Because one Jew -- Mordecai -- refused to bow down to him, he convinces the king to order the genocide of every Jew in the Persian Empire. If he had succeeded, a single bruised ego would have caused countless deaths. As for Mordecai himself, Haman built a huge gallows to hang him publicly for his perceived insolence. As the story unfolds, however, Esther saves the Jews, Mordecai is honored above all men, and Haman is hanged on his own gallows.
How many times do our own plans work out that way? I'm not just talking about those situations when you cut off your nose to spite your face, as the saying goes. I mean all those times you work and plan and it ends up being a terrible result -- the thing you wanted most and worked so hard to achieve ended up destroying you. Or, even worse: the times you tried to take someone down in anger and lost yourself and all you had in the process. We may be rational, thinking beings made in the image of a rational, thinking God, but it doesn't mean we're smart 100% of the time. Sometimes our pride convinces us to go to great lengths simply to end up being our own undoing; we hang ourselves on our own gallows.
Avoid Haman's gallows. Listen to the Holy Spirit and discern what God truly wants you to do. Then do it. Plan how to get it done if the situation merits it, but only plan according to the direction of the will of God. Don't stick with a mistake simply because you spent a lot of time making it. Let it go and follow God.
Work hard. Do well. Do good. But don't kill yourself in the process. Remember Haman's gallows.