What finally got you to lower your chin?

After months of being told to drop my chin, and thinking I was, two things happened today:

1. Took a sharp right hook right on the jaw.

2. Saw a video of myself sparring, and it was head-up city.

I’ve tried shadowing with a tennis ball, which killed the habit during mits/bag/shadow. I hope that after today I will keep my chin down.

So what was your moment?