I love this post by Ben at The Overflow.
“After interviewing several developers, a pattern started to become clear: great developers share a lot. This takes different forms for different people but is very often a blog. “So what?” you might say, you would expect successful people—“thought leaders”—to use their position and platform to share their own ideas and projects. But the interesting thing is that for many top developers, their sharing mindset came before their success, and was the direct cause of it, not the result of it.”
Ben shares two powerful thoughts:
1) The most successful people give more than they take.
2) Sharing makes you stronger.
If you’re looking for two emotive messages to encourage more contributions from top members; I’d try these.