I've been a SWE for 12 years and has been teaching people how to code during my free time ever since I started coding (so more than 12 years of teaching).

I have taught around 30 students over the past 12 years who went from knowing nothing to getting a SWE job and from my limited dataset I have observed that:

1. Students who were taught for/while loops first has a hard time grasping recursion. I suspect it is because following the recursive callstack gets tricky and feels unintuitive. This inspired me to try a curriculum where I teach students recursion first and don't expose them for/while loops until they are prepping for interviews.

2. Students who were taught recursion first has no problem understanding for/while loops when they were exposed to it.

For people who are curious, I used to teach students at my local library but recently created a free online curriculum at: https://c0d3.com