How did you go from being an adequate to exceptional programmer?

I think being great at something isn't really something that you can teach. I also think that very few people hit a brick wall and stop being able to learn how to be an exceptional programmer. If you ask people that are REALLY good at something how they are so good, more often than not they'll shrug their shoulders and will probably tell you they don't know.

For me, the only way to become really good at something is to keep learning, and to ensure that you know of your own failings. If you don't know what you don't know, you won't try and fix those holes in your knowledge.

If you are aware of what you suck at, it's easy to pick that knowledge up through experience. If you are going through the motions and aren't finding yourself challenged, it's extremely easy to not learn anything of use. An exceptional programmer will have probably spent most of their careers working on problems they didn't know the answer to, and as a result have built up a huge body of knowledge.