When you are just starting out in your career, you ask dumb questions, mostly about the mechanics of the work that you’re doing. You’re too busy building the right intuition, so people only give you easy, well-defined problems to tackle.
As you progress in your career, however, you start asking more and smarter questions. This is when people start giving you ill-defined problems, where you may not have all the tools to solve the problem right away, but everyone around you trusts you to figure things out.