McDonald’s practically invented the concept of fast food. It promised meals that were inexpensive and convenient, that could be eaten on the go and even with one hand while driving. The food wasn’t necessarily healthy, but it didn’t need to be. Now, nearly 70 years after the chain was founded, people everywhere — and Americans in particular — have higher expectations about quality and taste. Our aspirations have evolved. This is part of the “customer relevance” problem that led to CEO Don Thompson’s resignation.