The social reasons for the recent transition in HRM are the need for global mobility which enables companies to transfer employees across border and also build local leaders who have skills and understanding of other cultures.
Economic reasons are to involve HR in key business planning decisions so that they can make a profit and increase their efficiency within the organization.
The evolution of recent HR functions has tended to be focus on cost savings rather than changing to a more business driven HR function such as investing in HR technology, giving HR the training and skill, etc.