A brand is a promise to the consumer. It’s the umbrella under which all products must shelter. All the people responsible for a brand must ensure that it meets that promise. The Toyota Prius is a promise of reliable transportation that achieve high-mileage with low emissions. So it’s no wonder that Toyota has decided to stretch the brand to other vehicles. Oh, wait, the Prius isn’t a brand. It’s a model within a brand, which contains other examples of reliable transportation that achieves high-mileage with low emissions. Is that confusing? Well if it isn’t now, it soon will be. “The Highlander hybrid and Camry hybrid do OK, but calling it ‘Synergy Drive’ never resonated with consumers,” veteran Toyota dealer Earl Stewart told Automotive News [sub]. “But they can make hay on the Prius name. It’s a magic name. If somebody says ‘I drive a Prius,’ everybody knows what he means.” But for how long? The truth about a brand is that its products must fulfill the brand’s promise, or the brand dies. Confusing that brand diminishes it and alienates the people who gave birth to it in the first place. Maybe not straight away, but eventually. And forever.