"Since there was a recession at the time, I thought I probably couldn't get a really good job and should try to settle for a lesser position. I found that even though I interviewed for positions for which I was unusually well qualified, I couldn't seem to get any job. I finally realized that I couldn't get these jobs because I didn't really want them."And:
"I discovered that it was easier to get this better position because they could tell I really wanted it. I learned that if you shoot for what you want, you stand a much better chance of getting it because you care much more."Both quotes are from an interview with Michael Marcus, a successful trader who was interviewed in Market Wizards by Jack D. Schwager.
Of course many times you can show how much you really want the job and still not get it. Then there's the advice that says you shouldn't appear too needy because nobody likes desperation.
I think the larger point is that you should pursue what you really want (job, self-employment, project, art, etc.), and work to improve your chances of success if at first you don't succeed.