First they bring out coke, people think 'omg its like got soo many calories in it'
so they bring out diet coke, people think 'omg its like got caffine in it which is a drug!!11'
so they bring out caffine free diet coke, which contains none of the elements that make coke taste like coke
Now they bring out vanilla, lemon, and all the other sad attempts at trying to decrease how hopelessly entrenched their brand is. Noone will bother with anything but the established coke and diet coke, I don't understand their marketing philosophy.
I think vanilla coke tastes like eating a candle btw.