My online journals fail. That's a fact. I write stuff anyone's OK to read for a bit, and everyone reads it. Then things gradually happen that not everyone really can read. Then there's nothing left that people in general can read. And I stop writing.
Don't cry wolf.
Don't waste all your antibiotics because you're breeding stronger bacteria.
Don't teach others that stereotypes aren't true because they might believe you.
Don't maintain that people are bad, because then we grow to be so immune to that fact.