There are a lot of these lists out there. I thought I'd throw my hat in the ring as well with my perspective. I think the hardest thing was limiting the list to 10 items!
Knows the design principles and patterns - design has rules and best practices. It amazes me how many people are not aware of this, or only partially understands design principles. Also, the many people who don't know what a design pattern is and when it should be used. This isn't new information. :)
Observes the world - The world is full of curiosities, both people and things. Explore this. Learn some human psychology. Notice things. Don't get to caught up in your phone.
Visualizes ideas - I love maps. I even have a few big books on just different types of maps. Maps are one way of visualizing an idea. UX Design has multiple ways to visualize ideas, whether it is sketching, task analyses, user flows, or something else. Use these things in your work. It's not just wireframes.
Experiments - We know we are not the user. But keep in mind there are also many, many, different users and not one solution will work for everyone. Hypothesize. Write your assumptions and expectations down. Try more than one idea.
Validates assumptions - You laid out your assumptions. Now be clear on how and what you are going to test. Why did you choose this method? How is it better than another?
Communicates well - both visually and with words. Not like you have to be an artist. But be clear with concepts and ideas. Be persuasive with your words. Be kind.
Wants to solve problems (for people) - UX Design is about solving people problems, not technology, not business. Those are a part and need to be taken into account, but first it's about people.
Knows how to prioritize - Along with prioritization, I think organization is a key skill as well. Can you think critically and analyze things? Can you organize your thoughts and your deliverables?
Doesn't pretend to know everything - We are always learning. Enough said.
Has empathy - Empathy for users, for coworkers, for stakeholders, for yourself.