People have cognitive processes, of which they are less than fully aware.
During sequential decision-making, their preferences change in ways that the individuals cannot foresee. As a result, people act in time-inconsistent ways. Some people attend a cult meeting just out of curiosity, with no intention of joining the group. At the end of a series of meetings, they do join the group. If they could have seen the change in their preference, they would not have attended the first meeting.