Researchers John Hayes and and Benjamin Bloom have written that it takes about ten years to develop expertise in any of a wide variety of areas.
I’ve never considered myself truly an expert. Often, I’ll hear myself being introduced to our clients as the Oracle expert, which always surprises me, because I know there are so many dark corners of an Oracle database in which I have no idea of its workings.
By another measure, an expert is someone who is no longer obligated to follow conventional wisdom. Owing to his or her mastery of the subject matter, an expert is allowed to forge off the well-worn path, and develop in new and novel directions. Over time, perhaps these novel and unique directions may eventually become the new conventional wisdom for others to follow.
I’ve never considered myself truly a rowing expert, although I have spent at least a decade on-and-off with crew rowing. I’ve rowed stroke; I’ve coxed; I’ve coached; and I’ve taught. My rowing charges probably do view me as some sort of authority in rowing since they are learning from me how to row. They ask me questions for which I have well-reasoned answers. And I have gone off in my own direction on developed what I think are the best techniques for moving the boat through the water. Yet, I know I still am not fully an expert.