They probably make more money writing lots of individual books about all the aspects of living life as a dummy.
If they came up with a "Life for Dummies", they would have to sell it in a series, like volumes of encyclopedias.
Actually, that isn't a bad idea.
Learn to laugh at yourself
We're all dumbasses, nothing but artificial intelligence is going to change that.
Most don't need a book if they have a mirror
aren't you a bit too old for that **** ?!
I'm not too old but I don't want such book, that's the point XD