Clearly productivity. But as a refinement, productivity without documentation is called a hack, not a great development.

Documentation - a significant amount of work ends up being maintenance. If you cannot explain why you did something, or refuse to waste your time explaining, then you are a poser. Chesterton's fence IS a critical problem. If you do not document why, you condemn those that follow to throw your crap out and just redo all of it.

Willingness to learn. The world is not stopping anytime soon. Each year you do not advance, you are going backwards.

Sorry that is 3 one things, I just did not want to post 3 times :-)

In today's world? Using AI while ensuring CYBERSECURITY. A good dev will always create code that is secure rather than just shipping it fast!

You mean other than knowing what you're doing? It's hard not to bring that up when it comes to vibe coding and the resulting contemporary ideas of what it means to be a "dev" or "coder".

If I had to name only one coding habit that distinguishes a great dev, I'd say it's in the ability to say no to the things that don't actually matter. Software isn't just about solving problems; it's about solving the right problems, which almost never means solving every problem, in spite of the greatest wet dreams of product managers and senior leadership. Jira is what you get when you believe that software is about solving everyone's problems.