A criticism of some positivist and structuralist theories is that they are deterministic: that they suggest that an outcome is predictable and inevitable. Many, particularly action theorists, would suggest that, because people have agency, no theory can predict human behaviour entirely accurately. For example, while labelling theory suggests a self-fulfilling prophecy, its adherents would always suggest that individuals could also choose to reject a label because they have agency and therefore the theory is not deterministic. Some argue that Marxism is deterministic as some Marxists suggest that a communist revolution is inevitable (although other Marxists dispute this). "March of Progress"-type functionalist theories, like Young and Wilmott's theory on the developmental stages of family form or Walt Rostow's 5 stages of development that are at the heart of modernisation theory are other good examples of sociological theories that are accused of being deterministic.