In medical school, an ongoing lesson is that there will be ongoing lessons. You're never done. Surgeons and internists are expected to keep studying for their entire career—in fact, it's required to keep a license valid.
Knowledge workers, though, the people who manage, who go to meetings, who market, who do accounting, who seek to change things around them—knowledge workers often act as if they're fully baked, that more training and learning is not just unnecessary but a distraction.
The average knowledge worker reads fewer than one business book a year.
On the other hand, the above-average knowledge worker probably reads ten.
Show me your bookshelf, or the courses you take, or the questions you ask, and I'll have a hint as to how much you care about levelling up.