According to psychological research, we humans will feel very happy because of unexpected rewards, which is obviously stronger than regular rewards. This discovery is widely used in salary management system. Fixed monthly salary is the basis of maintaining labor relations and cash flow of employees' livelihood, while the unknowns of bonus, commission, salary increase, performance, commission and year-end bonus are the key to incentive work. By the same token, we will look forward to sudden happiness stimulation more, and feel bored with regular happiness stimulation. It is also easy to endure regular pain, and more often afraid of sudden pain. For example, we all know that injections will speed up recovery, but we still choose to take medicine, because taking medicine will prolong our sickly state, but it is a regular pain, while injections are a sudden pain that we have a choice to avoid. Outdoor live broadcast is the application of random stimulation. Outdoor, contingency and unknown are countless times higher than indoor. More curious, more likely to produce dramatic plot development, that is, random stimulation that makes us want to stop.