I spent twelve years teaching Physics and Chemistry to secondary students in Ludhiana. Then I became a web developer. People ask me what transferred. This is the honest answer — not the LinkedIn version.
Breaking things down. Teaching forces you to understand something at multiple levels simultaneously — the intuitive level (so students get the concept), the formal level (so you can explain the mechanism), and the common-misconception level (so you can preempt the wrong mental models). This is exactly what good code review requires. It is exactly what good API design requires. It is exactly what good documentation requires.
Comfort with 'I do not know yet.' In a classroom, a student asks a question you do not know the answer to. You have two options: fake it, or say 'I do not know — let us find out.' The second option is more honest and teaches students that expertise is a process, not a state. I took that into development. I am comfortable saying I do not know a thing, finding the actual answer, and then explaining it properly.
Speed. A classroom runs on your schedule. A production bug does not. The first time a client's site went down at 11pm, I discovered that twelve years of 'prepare the lesson the night before' had not prepared me for incident response under real time pressure.
The knowledge hierarchy. In teaching, you are the expert in the room — students defer to you. In open-source, forums, and PRs, everyone is simultaneously an expert in something and a beginner in something else. The status dynamics are completely different. I had to unlearn the teacher-in-the-room dynamic.
Twelve years of explaining things. Not just knowing them — explaining them, to people with zero prior context, under time pressure, in ways that actually land. When I write documentation, I think about the twelve-year-old who asked me why a magnet sticks to a fridge. When I write a README, I think about the student who did not understand the formula but understood the analogy. That skill is not taught in bootcamps. It is earned in classrooms.
I would not trade those twelve years. They are why I write code the way I do.
Full-Stack React Developer building SaaS and usuable apps.