#3 really resonates with me, writing about topics that I think I know well enough to share online often reveals gaps in my understanding and new insights.
I used to think that application was the best way to fully understand a topic, but I think writing is equally important and effective.
1. It was fun
2. As a student it let me put my thoughts out there and hear other people's thoughts. Forum discussions kinda sucked by comparison.
3. It gave me a reason to really drill into something. The "if I'm wrong it'll be embarrassing" forced me to really learn what I was saying