LIMITATIONS AND FUTURE RESEARCH DIRECTIONS
The study has four limitations. First, as a cross-sectional study, it is restricted from inference of causality of the relationships. Future studies are encouraged to conduct longitudinal approach. Second, since our sample only involved banking firms in Hanoi, Vietnam, the results cannot be generalized to organizations in other industries. This is due to the varied degrees of competition per industries (Nguyen, & Papadopoulos, 2011), which may affect organizations’ investment in internal marketing practices. Neither can the study's findings be generalized to Western economies, the cultures of which are characterized as individualism and low power distance, apart from Vietnamese cultures with high collectivism and high power distance (Wang, & Yi, 2011). We suggest future research attempt a replication of our study using larger samples. We also recommend that researchers design cross-cultural studies to gain a comparative insight of the validity of the proposed model. This is because internal marketing effects in different cultures may vary (Awward, & Agti, 2011). Third, while our study's title addresses customer behavioral responses, which is rather large in scope, we merely pursued three behavioral outcomes. Future research may expand our study's design with additional behavioral outcomes like customer citizenship behaviors. Finally, while customers may produce both positive and negative WOM (Buttle, 1997), and organizations need to make efforts in managing both of them, our study deals with only positive WOM. We suggest that future studies either specifically attend to negative WOM or group certain negative customer behaviors including negative WOM and switching behaviors to study in relation to internal marketing.
