Coca-Cola is rolling out a new version of Coke Zero across the United States.
The company is trying to keep up with consumer trends and stay ahead of the competition.
But when they make changes, they run the risk of upsetting loyal customers and chasing them away from the brand.
PepsiCo learned that in 2015, when it removed aspartame from its Diet Pepsi formula in response to consumer complaints about the ingredient, it brought it back the following year.
The brand has to be careful not to stumble again today and remind the company of the 1985 New Coke debacle, when New Coke was introduced.