Why You Keep Old Phone Numbers in Your Contact List

I recently noticed that I add phone numbers to my contact list very often, but I never delete any phone numbers. The most important reason seems to be the amount of effort that it takes to delete phone numbers. This phenomenon of reducing the amount of effort seems to influence many aspects of our lives, including our health and well-being. I will discuss some strategies to improve your health, wellbeing, and contact list hygiene.

Golden Behaviors

– Nudges for a Healthy Lifestyle –

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I add new phone numbers to my contact list frequently. Before calling someone I have not called before, I add the phone number to my contact list. Also, after I answer a call from an unknown number (but now known), I usually add this number to my contact list. Very convenient if I want to call these people again and also convenient to see who’s calling if they decide to return my call. This behavior results in a list of 581 phone numbers that are currently stored in the contact list of my mobile phone. Adding phone numbers to my contact list has immediate benefits.

On the other hand, there are many numbers I never use. However, I never remove phone numbers from my contact list: never! Even though there are many phone numbers I never use. Moreover, there are some numbers I know to be incorrect or even obsolete. I still have the phone numbers of former colleagues from 7 years ago, who do not work at that company anymore. Their phone numbers probably belong to someone else now: strangers to me. Why keep the numbers of unknown strangers in my phone?

The ease of adding and removing phone numbers

Why is it so much easier to add numbers than to remove numbers? After all, it should be far easier to remove a contact (press the waste bin and confirm to delete) than to add a contact (type in name, adding an affiliation is useful, type in the phone number).

The simplest reason is that I just did not bother to erase the phone number when it turned obsolete. It just does not seem to be worth the effort of deleting the contact. I experience what psychologists call present bias: people disproportionally overvalue immediate rewards, while assigning less value to long-term consequences. For example, you might prefer to receive ten Euro today over receiving fifteen Euro tomorrow, but wouldn’t mind waiting an extra day if the choice were for the same amounts one year from today versus one year and one day from today. Thus, waiting one day is not worth 5 Euro to you and you prefer 10 Euro now. However, receiving an extra 5 Euro for waiting one day somewhere in the future is worth waiting for. This is behavior seems inconsistent: with everything else similar you are willing to wait for an extra 5 Euros one day, but not another.

We are present biased for effort

Most research on present bias is done with monetary rewards, such as in the previous example. However, we also have a present bias for effort: we disproportionately overvalue spending less effort now, while assigning less value to spending more effort in the future. Ned Augenblick is a professor in behavioral economics at the Haas School of Business at Berkeley California. He and his colleagues had people allocate tasks to three different time periods: the first set of tasks should be completed right away, the other two time periods were after a week and after two weeks. At the beginning of the second period, people could reallocate their tasks to be completed right away or postpone them to the week after. People showed present bias for effort: they reallocated about 9 percent less tasks to the present period than their initial allocation a week ago.

This explains why deleting phone numbers now, does not seem to be worth the effort. I consider it to be a waste of time to do it immediately. When I hear a former colleague has a new phone number, I disregard the effort it will take to delete it in the future. This future effort could include remembering which former colleagues left the company and whether I currently have their old phone number or already updated it with their new phone number. Adding new numbers to my contact list has immediate benefits, whereas future disadvantage of deleting old numbers right away are not so obvious.

We are present biased for our health

Present bias can also affect our health. We all know this and all ignore this from time to time. One cigarette today is only marginal disadvantageous to our overall health, so we smoke one more. One beer today only has a very marginal detrimental effect on our overall health, so we drink one more. Studies show that many individuals do not follow the guidelines, even when they suffer from chronic diseases. They expect that failing to follow the guidelines today does have a negligible effect on their course of their illness. In this way present bias can explain low adherence rates to health care guidelines.

Strategies for dealing with present bias

Combatting present bias can be quite challenging. You have to forgo short term benefits to achieve long-term goals in health, wellbeing, and contact list hygiene. Here are some strategies that may help you overcome present bias.

  1. Pair activities for long-term goals with an enjoyable short-term reward. Kaitlin Woolley from Cornell University and Ayelet Fishbach from The University of Chicago Booth School of Business studied the effect of short-term rewards on long-term goals. They studied high school students that completed assignments in their statistics and geometry classes. When the teacher provided immediate rewards during the assignments – such as colored pens, healthy snacks (e.g., fruit snacks, granola bars, pretzels), and relaxing music was played – students were more persistent in completing the assignments than students that did not receive these immediate rewards. Thus if you pair activities for long term goals with enjoyable short-term rewards you are more likely to reach that long term reward. An specific strategy to increase healthy behaviors can be found in my blog about using a tempting habit to start a healthy habit.

  2. Aim your attention at daily goals. To achieve your long-term goals, you need to complete your daily goals. You will experience no presence bias – or at least far less presence bias – if you only focus on today. If you complete your daily tasks diligently than you will get closer to your long-term goal each time. Each time you do not smoke a cigarette, you come closer to the long-term goal of quitting all together. Each time you have completed a 30-minute walk, you come closer to the long-term goal of having a healthy lifestyle. The more you complete your daily goals, the more it becomes a habit.

    Of course, you should not postpone your daily tasks until tomorrow, like the people did in the experiments of Ned Augenblick discussed earlier. In such cases commitment may help.

  3. Commit yourself privately or publicly. Most people seem to know that they are present biased. Also, people in the experiments of Ned Augenblick that were more present-biased, made significant more commitments to stick to their original allocations. Ned and his colleagues did this by allowing the people in the study to punish themselves if they did not meet their initial allocations. In other words, these people choose to receive less monetary compensation if they did not stick to their original allocations. So it seems that people who are more present biased, also are more likely to make commitments to themselves or others to counteract the effects of present bias. Making more commitments thus led to reducing the effects of present bias.

    So you could commit yourself privately, by making similar commitments yourself. For example, you could commit to putting one Euro in a jar every time you do not meet your daily goal. From time to time you donate the contents of the jar to charity. You can read more about how spending money can be beneficial to your health in a previous blog.

    Or you could commit yourself publicly. Tell your partner or your friends about your daily goals and ask them to keep you accountable for attaining these goals. More details can be found in a previous blog about how I committed myself to running.

Why You Keep Old Phone Numbers in Your Contact List

So the first reason why I do not delete my old phone numbers is present bias for effort. The second reason is that it would feel very abrupt – even insensitive – to erase old phone number right away. For deceased relatives you need some time to grieve before you can erase their phone numbers. And combined with present bias for effort that you experience: why would you delete them? You can always do this later… right?

If you are the kind of person who likes order in his contact list you could apply the following strategy. You could commit yourself to delete the number from your contact list on the day that you learn it is obsolete. I will give you a minute right now to make this commitment to yourself. If you want to take it one step further and also more effective, then you can use this minute to make this commitment public: just say so in the comments.

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Niels Vink (1975) is author of Golden Behaviors and behavioral designer. He uses insights from the behavioral sciences to explain why people often act against their own interests. As a behavioral expert, he explores how you can nudge your behavior for a healthy lifestyle. He has Master degrees in Social Psychology (Leiden University) and Industrial Design Engineering (Delft University of Technology) and holds a PhD in Consumer Behavior.

When you have been inspired to start and maintain your Golden Behaviors, reach out to me.

Source of top image: Photo by PhotoMIX Company via Pexels


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