I guess I've never understood why "failure" was such a bad word to begin with. I've learned some of my most important lessons from failure, and failure has often helped me to succeed in my life.
I failed Algebra in the 7th grade. It was the first time I'd failed anything, having breezed through grades 1-6 with pretty much all "A" grades. But Algebra kicked my butt. I was pretty devastated to learn there was something I was not naturally good at. I went through a couple of years of, "who cares, and who needs it", but finally conquered it with a "B" in the 10th grade. I practiced it and other math on my own time until I got better at them. Today at 45, though I'm not a math genius, I'm better at math than most of my friends and coworkers, including those who breezed through math in school with "A" grades.
When I built my first computer, back in the day before they color coded the power connectors to make them idiot proof, I immediately fried the motherboard because I was an idiot. Never made the same mistake again. Today I'm considered a "computer guru" by friends and coworkers (though reading computer related posts by some of you here, I still scratch my head and think I'm an idiot).
Failure is often one of the toughest of lessons, but it's also often one of the best learning tools we have.