Coke's product is less sweet than Pepsi. What that means is that if you're drinking a lot of soda, Coke takes much longer to start tasting repulsive than Pepsi does, even though at first sip Pepsi might taste more delicious for some.

That was what led to the New Coke disaster. In taste tests, five out of seven people tested preferred the New Coke taste, because it was sweeter. But when rolled out, people found it got old fast. And while now New Coke is seen as a branding disaster, the truth is if it had been a more appealing product, the brand would have caught on and it might have led to a rout of Pepsi. While most of a brand is perception, the product does matter somewhat.