Atul Gawande is my favorite overachiever. He's a surgeon and writer for The New Yorker, but those aren't the reasons I admire him. I like him because of this statement: "Betterment is a perpetual labor." No matter how good one might be, he asks us to ask ourselves, "How can you be better?"
His 2007 book "Better" chronicled part of his journey towards becoming a doctor, and it gave a lot of advice for those pursuing a career in medicine, but I think this book should be required reading for all humans. Here's a passage from the afterword, which to me sums up the concept behind the book.
In medicine, just as in anything else people do, individuals respond to new ideas in one of three ways. A few become early adopters, as the business types call them. Most become late adopters. And some remain persistent skeptics who never stop resisting...I am not saying you should embrace very new trend that comes along. But be willing to recognize the inadequacies in what you do and to seek out solutions.Of course, if you think you've got a good overview of the book just from reading this post, reading the entire book will make you that much better.