Actually, a lot of things are like this...

When you learn to drive a car, you start all nervous on your L plates. You play it safe, ask lots of questions, and drive well under the speed limit by accident. Then you get your P plates (at least, this is how it works in Australia). All of a sudden, you have no supervisor, a higher maximum speed limit, and previously unknown independence. You gain confidence, start to push boundaries, show off a lot, and generally think you're unbeatable.

Then something happens. Maybe a close call, maybe a crash. Maybe just further general experience.

It may not even directly happen to you, but for whatever reason, you suddenly realise you are far more inexperienced than you thought. You slow down, you take your time, you accept that you never stop learning. You are humbled, and what you do next can either broaden your horizons, or close them off forever (in this field, anyway).

I have recently been given some programming code by people who are professionals. I can follow it, even though it's an unfamiliar language, and I'm proud of that fact. However, I can also see a level of professionalism in their work that I have yet to attain. I have been programming, almost entirely self-taught, for over ten years. But, until now, I have never really seen how a professional does it. I am humbled, I realise I have far more to learn than I thought, even after so long. What will I do about it? If I'm serious about programming as a career, I need to use this as a spring-board for my education. I could let it depress me, but then I'd have nothing left. So my only choice is to improve.

And I actually feel pretty good about it.