The anchoring effect arises as the result of a heuristic, that is, a guiding mechanism that our brains use when we are required to make a decision.
From the point of view of evolution, resorting to heuristics makes perfect sense, because in lots of situations we simply don’t have enough time to access, assimilate, and weigh up all of the information we need to make the best decision. In the Stone Age, when people saw a wild animal approaching, they had to make a snap decision: danger or no danger? It was a matter of life or death. And the same underlying principle still applies today. We all use rules of thumb and mental shortcuts to handle everyday situations.
They save us time and effort because they are subconscious processes and our brain handles them quite effortlessly. We only engage in conscious, controlled thought when something unexpected quickly grabs our attention. Think about it. As an experienced driver, you can drive to work each day as though you’re on auto-pilot, but if you encounter roadworks on your usual route, you notice immediately. Our brains fall back on heuristics when we are tired, distracted, or under stress.
So, the anchoring effect is a form of cognitive bias that arises from heuristics. Kahneman and Tversky assumed that it occurs because people do not sufficiently adjust their judgment in relation to the anchor. Later research contradicted this theory, and conflicting models exist to this day, meaning that the question of why exactly we fall prey to the anchoring heuristic is still a mystery.
One thing is certain though. There are other types of cognitive bias that influence us too, for example the IKEA effect, the halo effect, the decoy effect, the endowment effect and the bandwagon effect. And like the anchoring effect, all of these can be used in sales and marketing.