In order to combat forgetfulness, it is important to understand some of the major reasons why we forget things. Elizabeth Loftus, one of the world's most renowned experts on human memory, has identified four major reasons why forgetting occurs. One of the most common explanations is a simple failure to retrieve the information from memory. This often occurs when memories are rarely accessed, causing them to decay over time.
Another common cause of forgetting is interference, which occurs when some memories compete with other memories. For example, imagine that a woman just started a new school year as an elementary school teacher. She spends some time learning the names of each of her students, but over the course of the year she finds herself constantly calling one particular girl by the wrong name. Why? Because the girl's older sister was in the same class the year before, and the two look remarkably similar. It is the memory of the older sister that makes it so difficult to recall the younger student's name.
Other causes of forgetting include failing to store the information in memory in the first place, or even intentionally trying to forget things associated with a troubling or traumatic event.