A new investigation by the University of Pennsylvania has found that when it comes to favors, it is best to ask for them back as soon as possible, assuming we are not doing the favor as a purely selfless act. The study authors conducted a detailed experiment with many participants from a public hospital (all of them in a reasonable financial situation) who had undergone very expensive treatments. In exchange, the hospital would request a donation of any amount.
In one group they would ask for the donation just one week after the patient had undergone treatment, and in the other group, they would ask for the donation several months later.
The results were that every single person in the first group made the donation, and at a higher amount. For those in the group that were asked several months later, the researchers found that for every month that passed, the willingness to make a donation decreased by 30%.
Does this example apply to every-day situations? We think so, and in our view, the results of this study are not too surprising. The takeaway is very clear: the further into the future you get, the less likely someone is to repay a favor.