According to Paul Nunes and Brian Johnson, the authors of Mass Influence, most people generally buy with their emotions. Later, they justify their purchases with logic. In other words, people buy impulsively. They did not go into the store or go online planning to buy what they ended up buying. They were shopping for a particular item, but spotted something else. Curious, they examined it, and wanted it. So they bought it.
It is called impulsive buying.
Statistics state that 20% of what shoppers buy at the grocery store is bought on impulse. However, the numbers vary widely based on other factors, such as if the buyer drove to the store or rode a bike, whether they are young or old, married or unmarried, and whether or not they consider themselves browsers or “fast and efficient” shoppers. Shopping online versus shopping in a traditional store makes a difference too. This will be discussed in more detail below.