Greatest lesson you have learned from your worst actions inside world wide web

We manga readers... Whoever you are...
Surf in multiple sites encounter various things along side with it. Sometimes we tend to do mistakes while surfing sites, commenting videos, commenting shared things, etc. And after recognizing our mistakes, we took it y heart and soul to never repeat it again

My greateat lesson is to learn how to respect readers perception and their taste... It was a debate on a very controversal manga and yeah... I end up losing to one of commenters and I was attacked restlessly by another commenter/s
And another... Do not attack the person whom likes the thing! And juat debate on the aubstance presented...

What about yours? What's your greatest lesson from www mistakes?