What's the single most valuable lesson you've learned in your professional life?https://news.ycombinator.com/item?id=4288931 by caseya • 14 years ago 4 2 14 years agoNEnews.ycombinator.comhttp://www.quora.com/Whats-the-single-most-valuable-lesson-youve-learned-in-your-professional-life