Earlier this year, Paul Graham wrote an essay about feeling like a noob.
I resonated a lot with that essay, because most endeavors in my life start out with me feeling like a massive noob. The counterintuitive thing, of course, is that the better I seem to become at it, the more noobish I feel.
The interesting thing to me about this inverse Dunning-Kruger effect, which I believe often presents itself as impostor syndrome to many software engineers, is that it can serve not only as a forcing function towards improving even more but as an indicator as to how well you are doing.
Personally, if I begin to feel like I've mastered a certain skill then that is an excellent indicator that I am missing something entirely. I often feel more capable at things the more I practice, which I can use as a sign that I'm prepared to learn something even more difficult or advanced, but anything more than "feeling capable" is worrying.
With this in mind, I now try and learn things with the goal of feeling like I'm less knowledgeable of the overall domain. Like PG writes in his essay, "the more you feel like a noob, the better".