10 characteristics of a great developer

There are plenty of blogs on this issue, but here is my interpretation of the characteristics of a great developer. I have worked with a few, and I strive to become one myself.

1. Expert in communication. Can communicate successfully with any person on any level of any organisation.
   
2. Always looking for improvement. Even when things are great, they can always be improved.
   
3. Never (or rarely) present a problem without possible solution(s). It is easy to find problems, it may be hard to find good solutions.
   
4. Never (or rarely) say no to inquiries. Always takes time to help both the team, and the people around.
   
5. Is constantly critical about code. Always seek to improve his/her own code as well as others.
   
6. Thinks of every line of code as equally important. Never writes any code without purpose. Always rationalise every line.
   
7. Knows something about everything. May be an expert in one field, but has enough knowledge to have constructive discussions on the matter.
   
8. Constantly seeking new knowledge.
   
9. Constantly helping others become more knowledgeable.
   
10. Is always accountable for own actions.