Hertzberg suggested that there are some factors that motivate people leading to performance and job satisfaction and that there are another, separate factors, which prevent dissatisfaction. These "hygiene factors" such as organization policy, relationship with supervisor, work conditions and salary will, when adequate, prevent dissatisfaction. However, they alone are not sufficient for leading to job satisfaction. Hertzberg's theory of divide motivation and hygiene factors has been criticized for his methodology and for ignoring situational factors. Nevertheless, it is hugely read and is valuable in demonstrating that satisfaction and dissatisfaction are not necessarily two ends of the similar continuum.