While the study has provided a comprehensive portfolio analysis as the issues discussed above, some limitations must be acknowledged, leading to anchors for future research. First, like all the case studies research, to ensure higher reliability and validity, larger samples are needed to find out generic result for the entire logistics service industry in worldwide. Second, to further eliminate researcher bias and reduce information asymmetry, interview should be conducted with industry professionals. Finally, despite the efforts of data selected from enormous information available, there is still lack of precise financial figures in regards to economic performance. Further research should analyze financial performance on a better base with sufficient numeral figures and better model to see if more precise interrelationship could be concluded.