Strategy implementation considered most difficult stage in strategic management process why?

Strategy implementation is considered the most difficult state in strategic management because it involves change

In order to implement, it is essential that all support given by managers and the workforce when this happens, only then can implementation be possible. Hence, as long as the change is not receptive, implementation cannot take place. Therefore, more time is needed to induce the idea of change and this makes it as the most difficult aspects of Strategic Management. (by Ritz).