The 10,000-hour rule.
Popularised by author Malcolm Gladwell in his book 'Outliers', I suddenly saw it being mentioned everywhere. You've likely heard of it, too.
If I recall correctly, it's also splashed out over a wall in our Lifelong Learning Institute (LLI) building (in Singapore).
When I first heard of it, my immediate response was to think about something I was good at (or, at least, thought I was good at), and estimate-calculate the number of hours I'd put into it.
And...
I didn't quite hit 10,000 hours.
Did that mean that I wasn't really good at it?
I couldn't tell for sure, of course, and I didn't really want to go around asking whether I was good at teaching.
That seemed embarrassingly self-indulgent.
So, instead of wondering, I decided to double down on getting even better at it and, some time later, I started getting more and more positive comments and feedback about my style of teaching and my delivery skills.
I've stopped counting the hours.
Not because I think "I've arrived", but because teaching is something that I love to do and I've been consciously and purposefully testing methods and techniques over the many years I've been doing it.
Even if I'm not yet a "master" (by I-don't-know-whose standards), I'm certainly better than I was 15 years ago.
And that is good enough for me.