Why It Took Dunkin' Donuts 10 Years to Build the Perfect New Cup The inside story of the struggle the donut chain had in phasing out its iconic, yet hazardous, styrofoam cup.

In New England, it is often said, Dunkin' Donuts is religion. Not only does it have a rock-solid reputation for consistency -- the chain still uses the original coffee blend established by founder Bill Rosenberg more than 60 years ago -- it's also egalitarian, the sort of place where your car salesman grandfather and your techie nephew might run into Patriots owner Bob Kraft, all out for their morning Dunks run. This universal quality is part of what has helped the brand engender a ritualistic loyalty and retain a distinctly local vibe, even as it has expanded to more than 12,500 stores in 46 countries. It is also why Dunkin' does not take change lightly.

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This is not to say it hasn't made innovations over the years. You don't get this big without moving forward. But change is often slow, says COO Scott Murphy; it requires "uber-communication" with guests and inevitably results in an onslaught of hate mail anyway. "We have such loyal customers, who are coming four, five times a week," Murphy says. "When we don't get it right -- maybe we give them the wrong flavor coffee or a doughnut instead of a bagel or we change their cup…we change something -- it's a big deal," he says. Last year, for instance, when the chain announced it would be replacing its fan favorite Coffee Coolatta with something, in the words of then SVP of marketing Chris Fuqua, "better," called the Frozen Iced Coffee, customers accused it of "basically ruining everything."