Perceived ease of use is hypothesized to have a signifizant direct effect on perceived usefulness, since, all else being equal, a system which is easicr to use will result in increased job performance (i.e., greater usefulness) for the user. Given that a non-trivial fraction of a user's total job content is devoted to physically using the system per se, if the user becomes more productive in that fraction of his or her job via greater ease of use, then he or she becomes moreproductive overall. Thus, characteristics of the system may indirectly influence usefulness by affecting ease of use.