What I love about my work is that it requires creative solutions to often challanging problems.  And with each problem you solve, you collect experience that will be useful later.  So in that way, my real job is about "constant self-improvement."

    However, it certainly takes more than creativity to be successful. Often it requires a fair amount of stubbornness (or more politely: "perseverance") to work through a problem.  But as a programmer friend of mine likes to say, "Every problem has a solution."