Lessons learned from traditional MA

My martial arts path really started with WTF Taekwondo. And over the years, I've found certain deficiencies in my TKD training and bad habits I picked up from sparring semi full-contact for points. I've learned that a lot of traditional martial artists find a sort of cognitive dissonance with classical or sport training and some of the realities of fighting. That being said, I've found that there were lots of important benefits from my TKD training that I wouldn't trade for the world. And some of them have nothing at all to do with fighting. What are some of the lessons from your traditional martial arts training that you'll never forget?

I'd like to add that I've posted a very similar thread in the Korean TMA forum. I deliberately reposted it here because I'm curious about what sort of different answer I may get. I don't want just Korean MA fanboys answering my query.