John Sylvan told The Atlantic that he sometimes regrets his invention because it creates too much waste and is bad for the environment.
"I feel bad sometimes that I ever (invented the K-Cup)," Sylvan said. "I don't have one. They're kind of expensive to use. Plus it's not like drip coffee is tough to make."
How expensive? A 12 pack of Folgers K-Cups, for example, sells for about $6.72, giving you about 4oz of coffee. In comparison, a 33oz container of Folgers Classic Roast Ground Coffee sells for about $8. That's 8 times the amount of coffee for nearly the same price.
But most Americans don't seem to care about the cost or the environmental impact of K-Cups. The Atlantic says K-Cup brewers are now in 1 in 3 American homes.
"It's like a cigarette for coffee, a single-serve delivery mechanism for an addictive substance," Sylvan said.
Sylvan says his biggest regret is the environmental impact. The Atlantic says if all the K-cups sold last year were laid end to end, they would circle the Earth more than 10 times.
But Sylvan can't do much about that; he sold his interest in Keurig Green Mountain in 1997 for $50,000. The company now makes $4.7 billion in revenue.