How we change what others think, feel, believe and do
When we recall a past decision, we distort memories to make the choices we made appear to be the best that could be made.
Thus when we have selected from a set of options, we will attribute more positive and less negative attributes to the option we have chosen (and vice versa for options we rejected).
As a result, we feel good about ourselves and our choices and have less regret for bad decisions.
Older people tend more towards this bias.
I buy a car, based on a set of criteria I have developed. Later, I am sure that the car I bought passed more criteria than it actually did.
Mather, Shafir and Johnson gave subjects a choice between two job candidates, each of which had four positive and four negative attributes. When later asked to recall the attributes of these, the subjects recalled more positive attributes of their choice and more negative attributes of the candidate they had rejected.
Get people to make choices early on that they will use in the main point you want them to choose. Make these choices easy to make in the direction to support your later choice.
Think hard when recalling a choice, to remember the real reasons for your choice.