In summary, his research found that we tend to make poor decisions when we have recently experienced a negative emotion. That makes some intuitive sense related to the short-term impact on our decision making. Surprisingly, he also found that we tend to repeat those bad decisions when we are faced with them again in a later situation that was not preceded by a negative experience or emotion.
Here's the impact of his findings, if we make a snap or quick decision in the heat of the moment while we are angry, upset, or frustrated, we just might repeat that decision at a later date when we are not under the influence of a negative emotion. So, that one time snap decision can have a lasting impact on our businesses, families, and relationships.
Here's where I see the practical upshot of Ariely's findings, always check your emotions before you make a significant decision. Before writing that performance appraisal, evaluating those budget numbers, confronting poor performance, disciplining your child, or speaking with your spouse; check yourself.
Are you still angry from an earlier conversation with someone else? Are you irritated by the traffic on your drive to work? Did you just learn that you need to invest money you don't have to repair your car?
If so, be careful. You might want to take a few extra minutes to get your emotions in check. Take a walk, read something positive, or just get away from the situation for a moment to carefully consider your emotional state and it's possible impact on your decision making.
The issue is bigger than the one decision in front of you at the moment. The issue is the potential to sow the seed of a pattern of decision making that could have a long-term negative impact on your relationships and performance.