For taxpayers using the manual method, lack of facilitating conditions such as access to computer and internet resources was the most significant barrier to eFiling usage whilst taxpayers using the electronic method reported perceived usefulness as the primary determinant in their decision to use eFiling.

http://repository.up.ac.za/bitstream/handle/2263/41578/Jankeeparsad_Acceptance_2014.pdf?sequence=1&isAllowed=y