it's difficult to select tools
It is quite difficult to select appropriate decision tools because there aren't only one rule in doing this. Different people have difference opinions towards this. Obviously, the selected tools must suitable for the problems, that is these tools is useful to solve out this kind of problems or under this kind of environment, these tools is effective. But this is not enough. The tools must also fit for the decision makers. In fact, it is the decision makers who choose the tools and use them. If they don't prefer or they aren't familiar with the tools, they aren't able to use it effectively. Sometimes, the feeling of boards must be considered. For example, AHP is criticized by the unclear results. The people who conducts it have no problem with how it be presented, however, if the boards do understand this tool at all, it will be difficult for them to understand it within several slides.