Interesting article here:
http://www.theguardian.com/news/oliver-burkeman-s-blog/2013/dec/11/ironic-effects-sabotage-your-plans
Particularly this paragraph:
Awareness campaigns get forgotten by the people who need them most
"Motivated forgetting" is an especially galling species of ironic effect: when a message makes you feel vulnerable – for example, by reminding you of the ways in which your gender or ethnicity places you at a disadvantage – you're more likely to find ways, conscious or otherwise, to forget it, in order to retain a sense of self-control. In a study to be published in the Journal of Consumer Research, marketing experts found that students who were reminded of their university's poor performance were less likely to remember an advertisement offering a discount at the campus bookshop. "Consider an advertisement for breast cancer prevention," the researchers write. "If the ad makes … women’s vulnerability to the disease" salient in their minds, they could "feel threatened and exhibit defensive responses, such as decreased ad memory."
In short: if you're trying to change behaviour or beliefs – your own, or other people's – don't assume that the most direct, vigorous or effortful route is necessarily the most effective one. The human mind is much, much more perverse and annoying than that.