The Human Processor Model is a framework for system designers. It is a cognitive modeling method, which is also a possible way to evaluate the usability of a product, by estimating how long a person will take to perform certain tasks. The estimates are given by the framework, which eliminates the need to perform experiments with the users. Another aspect of the framework is that the designer can guess what the expected chance is that a person remembers an item that was presented to them in the process.  This can be used as an indication of whether or not a user is likely to recall crucial elements that they encountered during the procedure.

Source: Human Processor Model