The internal factors, Robisson (2006) suggests that work can identify employees' self-awareness and increase appreciation and rewards, but it depends on psychological factors which are the individual differences. The psychological contract consists of unwritten expectations that they can receive in exchange for their dedication to the organization. Briner and Conway (2004 cited by Robisson 2006: 21) assert that long-term job security is exchanged for employee loyalty. In terms of understanding the psychological contract, it is important to discuss external factors that can affect internal behavior.