So very this. I've been in the field for about 40 years now, but my moment of revelation was the wake of Y2K. At a stroke, I watched a bunch of my older friends wash out of the industry -- their skills (especially the COBOL programmers) were suddenly no longer in demand, and they had basically stopped trying to keep up many years before.

The lesson I took from that is that constant self-directed learning is the most important skill for any successful programmer. Since then, I've been very frank in all interviews that I expect to spend an average of an hour per day learning stuff, some of which will be directly work-related and some of which won't. The smart hiring managers recognize how important that is.