If you're job doesn't allow you to learn, it's dangerous to your career. There's no longer any job security in doing what you know.
Brazen Careerist: How to find a job you'll love, 2011-Nov, by Penelope Trunk
When people talk about their job, they are really talking about their learning. When we say, "What do you do?" we really mean what do you learn? Because that's what makes a person interesting – what they are learning. No one wants to answer the question what do you do if they have a job where they are not learning. That's how you know it's the learning that matters.