In PhotoSig.com a person asked how one can go from good to great. Here’s my response:
…the arts/crafts of exposure, composing, and telling a story are not something that one masters and then move on to the next thing. The same applies to the more specifically technical aspects of photography. One is always learning, deepening, exploring, creating.
Taking a great shot, in my estimation, can happen at any time. Sustaining a level of excellence however, and making great work, requires that we exercise ourselves beyond technique and beyond the usual, beyond the limits that mastery of what is present requires. It takes dedication and commitment yes, but also a level of performance and creativity that emerges from mastery of technical aspects and depth of reflection and creative risk. I hasten to add that those considered great, were not great at every moment, or with every attempt. But mastery of the technical, deep reflection, professionalism in effort and disposition, facilitates the development of inspiration and the sustainment of will that is foundational for excellence.
It might very well take a lifetime to master being darn good at one thing. You, and the others who have posted, are right that it takes commitment. But commitment to what? How is that commitment expressed? What form does it take for a particular artistic vision? How might you find what you can be great at (it is unlikely that we will be great at everything)? Who is to judge your work (whose judgment matters, and why and how, so?). I think those are some of the issues that I think are not jut incidental to your question. Unless, of course, you just meant how to get better or improve.
Finally, I think “great” is an accorded status. Not likely something you determine for yourself (unlike Muhammad Ali!. : )