The funny thing about writing the Scala Cookbook is that it started as a whim. I was just about to leave for a vacation at the beach, and right before I turned off the computer, a thought flashed in my mind, “I should contact the people at O’Reilly about writing a cookbook for Scala.” I then had a doubt that they would actually do it, but I applied the “What the heck” rule — i.e., “What the heck, what do I have to lose?” — and sent the email.
I dug around the internet for a few minutes, found the correct O’Reilly email address, sent them a message, turned off the computer, and drove to the beach. While I was at the beach the publisher wrote and said, “Love it, send me a full proposal!”
So if you’re thinking about doing something, but are afraid or uncertain about doing it ... apply the “What the heck” rule, and give it a shot. :)