The thin-market effect is further complicated by the fact that adults go into and out of the market very quickly. The prevalence of shopping convenience helps explain why 35 percent of shopping occasions are described as planned, while 65 percent are thought of as impulse or spur-of-the-moment. The time period between the decision to buy something and actually buying it is very short for consumers.
In 50 percent of cases, the decision to shop and to purchase is made on the same day. A much smaller number – 18 percent – of purchasing decisions are made as far as a few days in advance. Equally rare is a purchasing decision that extends over a more protracted period – only 18 percent of such decisions to buy are made as far as two weeks or more before the purchase.