Psychologist Burrhus Frederic Skinner conducted a series of experiments and proposed the well-known theory of behavior modification, which provides a theoretical foundation for designing with uncertainty.

Uncertainty refers to situations in which the outcome of an event or decision cannot be predicted in advance. Certainty gives users a sense of control, while uncertainty adds enjoyment and excitement to a product. The widespread presence of uncertainty introduces possibility and surprise, increasing user engagement and immersion.

Mechanisms such as lucky draws, bargaining games, and check-in campaigns in digital products all leverage uncertainty.

It is important to note that if uncertainty is used to enhance a product, most outcomes must still carry some form of value. The purpose of providing value is to ensure users perceive that the overall gains outweigh the losses; only then will they be willing to continue participating.