"Passion, drive, perseverance, experience, patience, brilliance, etc." You beat me to this list of qualities. The only minor disagreement is that brilliance sh

"Passion, drive, perseverance, experience, patience, brilliance, etc." You beat me to this list of qualities. The only minor disagreement is that brilliance shows up only after a good developer, who embodies your list of qualities, follows his/her interests and gets really familiar with a couple areas of the field. As an example, someone who enjoys hacking graphics at a low level will eventually become great at that area, but may be only good at language design. Our field is too broad to be great at everything.