When people infer that an event or behavior is due to unchanging, permanent factors. This theory is heavily based on outcomes both positive and negative. Some of the things that influence this pattern are as simple as luck and effort level.
Perhaps a person decides that if they walk under a ladder, they will not get into the college they want to attend (because the day before they walked under a ladder and got rejected from another potential school)…their behavior after walking under the ladder could be altered. For instance, they might stop studying as hard as they did before and therefore have a lower GPA. They might stop chairing school committee and withdraw from regular social events where they could make connections.
You can see how easily this behavior can turn into self-sabotage. On the other hand, if someone believes that if they carry around a lucky penny whenever they go on an interview for a new job (assuming they had received a good job in the past under these circumstances) it might boost their confidence so they give a great interview performance.