Explain and illustrate the concept of post-purchase dissonance with an example.

Examples may vary.
Dissonance theory can help to explain why evaluations of a product tend to increase after it has been purchased. Post-purchase dissonance can occur in situations where the consumer has a choice between more than one favourable alternative. For example, if the consumer narrows down her search for a new computer to two key alternatives and then selects one, dissonance can arise because the alternative she gave up (what researchers call the "forgone option") had many desirable qualities. This is because the cognition "that computer had some really cool options" and the behaviour "I picked something else instead" are inconsistent. This can lead to feelings of dissonance, which the consumer is motivated to resolve. One way this can be done is by reconfirming that she made the right purchase after all, focusing on desirable qualities of the chosen option and actually liking it more after it has been selected.