Researchers classified the three types of behavior. The first group, termed gamblers, took high risks but exerted no influence on the outcome of events. The second group, termed conservatives, were people who took very little risk. The third group, termed achievers, had to test the limits of what they could do, and with no prompting demonstrated the point of the experiment: namely, that some people simply must test themselves.

By challenging themselves, these people were likely to miss a peg several times, but when they began to ring the peg consistently, they gained satisfaction and a sense of achievement. The point is that both competence and achievement-oriented people spontaneously try to test the outer limits of their abilities.

— High Output Management by Andrew S. Grove