A number of critiques of the flexible firm model have been put forward. One problem is how to define the core and the periphery. Although this sounds easy in practice, an organisation will have a variety of employment contracts with different groups and distinctions become blurred. Although there is evidence that organisations are making more use of flexible working, 13 it is debatable whether this is the result of strategic decisions on the part of the firm in order to increase efficiency. More often it is about cutting costs and in some cases it is a response to a particular problem. In the National Health Service, for example, the old rigid shift system for nurses has caused major recruitment and retention problems. The response has been the introduction of more flexible working hours, temporary contracts, part-time hours and a return to nights-only contracts.
Another possible reason for increased flexibility in the labour force is that most of the
growth in industrialised economies over recent years has been through the service sector where part-time jobs are much more common. The flexible firm model was originally applied to the manufacturing sector. There are also costs involved in flexibility: the cost of training temporary staff, a possible lack of commitment on the part of temporary staff, and possible conflicts between temporary and permanent employees. A recent report which throws doubt on the benefits of flexibility in the workplace identifies these factors as counter-productive to the aims of flexibility.