Though the general location of clinics remained important, other 'external' motivators in particular peer pressure became relatively insignificant. With repeated performance of a voluntary act over time, the sense of personal, moral obligation assumed increasing importance. . . Similar findings were reported by researchers at the University of Wisconsin, who observed that the motivations of blood donors developed and changed over time. The results of their studies revealed that the greater the number of donations reported by donors, the less likely donors were to say that they gave so as not to disappoint others, and the more likely donors were to report that they were motivated by a sense of moral obligation and responsibility to the community. Whereas external motivations, such as social pressure, were likely to prompt the initial decision to donate, it was internal motivations, such as a sense of moral obligation, that maintained the behavior over time.
Donors learn to give by giving.
Moreover, learning to give in one context may carry over into other contexts. Several studies, for example, have found that active blood donors are more likely to engage in volunteer work or to make charitable contributions than non-donors. Further reading Aristotle. The Nicomachean Ethics. The process of commitment to regular blood donation.