Decision Fatigue

What is Decision Fatigue?

Decision Fatigue describes the deterioration in an individual’s judgement after a long series of decisions. Daniel Kahneman describes the phenomenon in his Thinking, Fast and Slow. When a person’s faculties are impaired by tiredness, distraction or stress (a process known as ego depletion), they are more likely to revert to less rational ways of solving problems. This means that people will rely on estimations and emotional responses after a long period of concentrated attention.

In a study published in 2011, it was shown that judges at a specific facility approved parole requests significantly more frequently when the decision was made directly after a meal. The rate of parole approval was around 65% immediately following a meal and fell sharply and consistently in the subsequent hours.

Examples

Knowing that consumers make more irrational decisions following long periods of concentrated attention is useful for both digital marketers and advertisers. The value of advertising based on direct propositions is likely to decrease at times when the audience is preoccupied, tired or under stress. Counter-intuitively, this suggests that the best slot for a television advert is towards the beginning of a boring programme.

However, the knowledge that consumers are likely to be more impulsive following a period of ego-depletion suggests that campaigns based on emotional messages or simple brand exposure are best placed towards the end of an engaging programme. One reason that app-designers increasingly favour in-app purchases might be that a user’s decision making faculties are impaired by using the app.