Holy cow, I wrote a book!
While signing up for online bill payment for one of the services I use,
I encountered the following check box:
Uncheck this box if you do not wish to
receive electronic communications from XYZ.
This is not simply a negative-sense checkbox;
it's a double-negative-sense checkbox!
What's wrong with this:
Send me electronic communications from XYZ.
Oh, right, I know what's wrong with it:
It's too easy for people to opt out!
Marketing is all about making users ask for something they don't want.