I use to think that "reverse psychology" was only useful on kids...naive kids. For example, eating a highly nutritious sandwich in front of the kids and then saying....hmmm....hmmm...delicious jut to get them to eat the healthy sandwhich instead pizza. Parenting
Later, I realized that its frequently used in professional sports, marketing, financial firms, schools, medicine and many other careers.
I didn't realize it was used in medicine until last year when I myself was in the hospital and I witness it being used by doctors, nurses, therapists on many patients.