The economic principle of satiation is the effect whereby the more of a good one possesses the less one is willing to give up in order to get more of it. This effect is caused by diminishing marginal utility, the effect whereby the consumer gains less utility

Utility

In economics, utility is a measure of customer satisfaction, referring to the total satisfaction received by a consumer from consuming a good or service....

 per unit of a product the more units of a product he or she consumes.

For example if someone buys a can of cola

Cola

Cola is a carbonated beverage that was typically flavored by the kola nut as well as vanilla and other flavorings, however, some colas are now flavored artificially. It became popular worldwide after druggist John Pemberton invented Coca-Cola in 1886...

they will enjoy it. If they then buy a second one they will enjoy it less, and so forth. It can continue to the point where drinking a can of cola becomes a negative experience, and beyond.