Why, according to Pfeffer in his article about competitive advantage through managing people, are companies often unable to achieve competitive advantage through the $13$ principles for effective management of people?

Question $20$ options:

successful implementation takes a long$-$term view and companies are under short$-$term pressures$$

the ideas are unrealistic

managers don't care about people

managers typically put the principles all into place at the same time rather than doing them one at a time

none of the above