Last weekend I attended the annual Abbotsford Photo Arts Club Photographic Seminar in British Columbia, Canada at which John Shaw was the featured presenter. If you get the chance, I highly recommend going to see him if he comes your way. John started out as a college professor before becoming a professional nature photographer back in the seventies. He is an excellent teacher and does a better job of making complicated things simple than anyone I know. I've been at this for some years now, so much of what John said was merely review for me, but I consider the seminar extremely worthwhile nonetheless.
One of the things John said that really made an impression on me was that the main difference between a professional photographer and an amateur is passion. I've thought about that statement a lot during the past week; it really rings true for me. Passion is what drives us to do what we enjoy. It's what compels us to continually improve our craft and makes us always strive to do it the best we can. The byproduct of course it better images, and this in turn provides a feedback as to our progress and a satisfaction in having done our best that makes us want to go out and do it all over again.
If you don't enjoy what you do (not likely since you've found me on the web and are reading this), probably none of this will make any sense. But if you do, let your passion drive you. It can take you far. Pretty nice when doing what you enjoy can in itself help you do it even better.