" Never understood that one"
It is in layman's terms "The psycology of advertising".
Billions of dollars in research has been done to learn what motivates consumers to want to buy a product.
Much of advertising is based on such research, which includes such factors as "association" (for example an attractive women in a car ad spreads her legs and says "Take me for a ride in your Lincoln".
Or simple repetition has also been proven to work very effectively to manipulate people's perception of a product and their need for it. Just over and over repetition impresses the brain to believe and adopt what is being promoted.
Logical, rational thinking has almost nothing to do with effectiveness of advertising.